Statistics in the workplace Essay Example | Topics and Well Written Essays - 750 words

Statistics in the workplace - Essay Example Health statistics gives information on the health matters of people. This means that every person is part of a health statistic. To get knowledge, an organization first gathers data, these data is processed into facts and figures which are transformed into information. Statistics has several other uses such as making decision on the relevant staffing needs of the hospital facility in relation to information or data collected frequency or number of patients a hospital has per period of time. Some of the many ways in which statistics can be used in rehabilitation health facility include: to carry out surveys on patient satisfaction or employee satisfaction, to carry out tests or experiments on new procedures just to mention but a few. There are various branches of statistics, the two main branches are; descriptive and inferential statistics. Descriptive statistics Descriptive statistics is a branch of statistics that describes data that has been gathered revealing the trends and patter ns of the information. Descriptive statistics illustrates how data is dispersed but does not test any hypothesis so as to form a conclusion on the basis of that data (Bennett, Briggs, Triola, 2009). In healthcare, descriptive statistics is used for various purposes. ... The patients who consent to the trial will undergo close monitoring during the study through close observation and evaluation. The results will be based on specifics such as the degree of side effects, rate of recovery and they are not charged for the process. Descriptive statistics basically uses aspects such as means of central tendency and dispersions these are mean and standard deviation respectively. In this example the mean will be used to give the overall impact of the procedure towards rehabilitation while standard deviation might be used to show how stable or unstable the drug may be. Stability simply means the uniformity in the way patients react to the procedure, therapy or drug. Inferential statistics is simply a method through which conclusions about an aspect of a population is drawn from a sample. A sample is a finite subset of a population. This is the procedure of selecting and using a sample statistic to draw conclusions about the population parameters and eventuall y the population. It is used when we have access to a sample but not the population. Statistical inference uses two methods namely; point estimate and hypothesis testing. The estimation method is usually used to inferences where information about a population is in the given sample. There are two kinds of estimates which are point estimate and interval estimate. The estimates are used to make inference on the population parameters. An example of point-estimates is the mean weight of patients in the hospital while an interval estimate is the range within which we expect the mean of a population to fall at some level of confidence say 95%. Hypothesis testing on the other hand is the

History and overview: Catalytic converter

History and overview: Catalytic converter A catalytic converter (colloquially, cat or catcon) is a device used to decrease the toxicity of emissions from an internal combustion engine. A catalytic converter works by using a catalyst to stimulate a chemical reaction in which toxic by-products of combustion are converted to less-toxic substances.First widely introduced on series-production automobiles in the U.S. market for the 1975 model year to comply with tightening EPA regulations on auto exhaust, catalytic converters are still most commonly used in motor vehicle exhaust systems. Catalytic converters are also used on generator sets, forklifts, mining equipment, trucks, buses, trains, airplanes and other engine-equipped machines. History The catalytic converter was invented by Eugene Houdry, a French mechanical engineer and expert in catalytic oil refining[1] who lived in the United States. Around 1950, when the results of early studies of smog in Los Angeles were published, Houdry became concerned about the role of automobile exhaust in air pollution and founded a special company, Oxy-Catalyst, to develop catalytic converters for gasoline engines an idea ahead of its time for which he was awarded a patent (US2742437). Widespread adoption had to wait until the extremely effective anti-knock agent tetraHYPERLINK http://en.wikipedia.org/wiki/Tetra-ethyl_lead-HYPERLINK http://en.wikipedia.org/wiki/Tetra-ethyl_leadethylHYPERLINK http://en.wikipedia.org/wiki/Tetra-ethyl_lead HYPERLINK http://en.wikipedia.org/wiki/Tetra-ethyl_leadlead was eliminated from most gasoline over environmental concerns, as the agent would foul the converter by forming a coating on the catalysts surface, effectively disabling it.[2] The catalytic converter was further developed by JohnHYPERLINK http://en.wikipedia.org/wiki/John_J._Mooney J. HYPERLINK http://en.wikipedia.org/wiki/John_J._MooneyMooney and CarlHYPERLINK http://en.wikipedia.org/wiki/Carl_D._Keith D. HYPERLINK http://en.wikipedia.org/wiki/Carl_D._KeithKeith at the EngelhardHYPERLINK http://en.wikipedia.org/wiki/Engelhard_Corporation HYPERLINK http://en.wikipedia.org/wiki/Engelhard_CorporationCorporation,[3] creating the first production catalytic converter . Metal-core converter Ceramic-core converter The catalytic converter consists of several components: The core, or substrate. The core is often a ceramic honeycomb in modern catalytic converters, but stainlessHYPERLINK http://en.wikipedia.org/wiki/Stainless_steel HYPERLINK http://en.wikipedia.org/wiki/Stainless_steelsteel foil honeycombs are also used. The honey-comb surface increases the amount of surface area available to support the catalyst, and therefore is often called a catalystHYPERLINK http://en.wikipedia.org/wiki/Catalyst_support HYPERLINK http://en.wikipedia.org/wiki/Catalyst_supportsupport. The ceramic substrate was invented by RodneyHYPERLINK http://en.wikipedia.org/wiki/Rodney_Bagley HYPERLINK http://en.wikipedia.org/wiki/Rodney_BagleyBagley, IrwinHYPERLINK http://en.wikipedia.org/wiki/Irwin_Lachman HYPERLINK http://en.wikipedia.org/wiki/Irwin_LachmanLachman and RonaldHYPERLINK http://en.wikipedia.org/w/index.php?title=Ronald_Lewis_(scientist)action=editredlink=1 HYPERLINK http://en.wikipedia.org/w/index.php?title=Ronald_Lewis_(scientist)action=editredlink=1Lewis at Cor ningHYPERLINK http://en.wikipedia.org/wiki/Corning_Glass HYPERLINK http://en.wikipedia.org/wiki/Corning_GlassGlass, for which they were inducted into the NationalHYPERLINK http://en.wikipedia.org/wiki/National_Inventors_Hall_of_Fame HYPERLINK http://en.wikipedia.org/wiki/National_Inventors_Hall_of_FameInventorsHYPERLINK http://en.wikipedia.org/wiki/National_Inventors_Hall_of_Fame HYPERLINK http://en.wikipedia.org/wiki/National_Inventors_Hall_of_FameHallHYPERLINK http://en.wikipedia.org/wiki/National_Inventors_Hall_of_Fame of HYPERLINK http://en.wikipedia.org/wiki/National_Inventors_Hall_of_FameFame in 2002. The washcoat. A washcoat is used to make converters more efficient, often as a mixture of silica and alumina. The washcoat, when added to the core, forms a rough, irregular surface, which has a far greater surface area than the flat core surfaces do, which then gives the converter core a larger surface area, and therefore more places for active precious metal sites. The catalyst is added to the washcoat (in suspension) before being applied to the core. The catalyst itself is most often a precious metal. Platinum is the most active catalyst and is widely used. It is not suitable for all applications, however, because of unwanted additional reactions and/or cost. Palladium and rhodium are two other precious metals used. Platinum and rhodium are used as a reduction catalyst, while platinum and palladium are used as an oxidization catalyst. Cerium, iron, manganese and nickel are also used, although each has its own limitations. Nickel is not legal for use in the European Union (due to reaction with carbon monoxide). Copper can be used everywhere except North America, where its use is illegal due to the formation of dioxin. How Catalytic Converters Work James L. Amos/National Geographic/Getty Images A large pile of platinum lined catalytic converters. See more green living pictures. There are millions of cars on the road in the United States, and each one is a source of air pollution. Especially in large cities, the amount of pollution that all the cars produce together can create big problems. To solve those problems, cities, states and the federal government create clean-air laws that restrict the amount of pollution that cars can produce. Over the years, automakers have made many refinements to car engines and fuel systems to keep up with these laws. One of these changes came about in 1975 with an interesting device called a catalytic converter. The job of the catalytic converter is to convert harmful pollutants into less harmful emissions before they ever leave the cars ­ exhaust system. Catalytic converters are amazingly simple devices, so it is incredible to see how big an impact they have. In this article, you will learn which pollutants are produced by an engine and how a catalytic converter deals with each of these pollutants to help reduce [edit] Types [edit] Two-way A two-way catalytic converter has two simultaneous tasks: Oxidation of carbon monoxide to carbon dioxide: 2CO + O2 à ¢Ã¢â‚¬  Ã¢â‚¬â„¢ 2CO2 Oxidation of unburnt hydrocarbons (unburnt and partially-burnt fuel) to carbon dioxide and water: CxH2x+2 + [(3x+1)/2] O2 à ¢Ã¢â‚¬  Ã¢â‚¬â„¢ xCO2 + (x+1) H2O (a combustion reaction) This type of catalytic converter is widely used on diesel engines to reduce hydrocarbon and carbon monoxide emissions. They were also used on gasoline engines in USA market automobiles until 1981. Due to their inability to control nitrous oxide NOHYPERLINK http://en.wikipedia.org/wiki/NOxx, they were superseded by three-way converters. [edit] Three-way Since 1981, three-way catalytic converters have been used in vehicle emission control systems in North America and many other countries on roadgoing vehicles. A three-way catalytic converter has three simultaneous tasks: Reduction of nitrogen oxides to nitrogen and oxygen: 2NOx à ¢Ã¢â‚¬  Ã¢â‚¬â„¢ xO2 + N2 Oxidation of carbon monoxide to carbon dioxide: 2CO + O2 à ¢Ã¢â‚¬  Ã¢â‚¬â„¢ 2CO2 Oxidation of unburnt hydrocarbons (HC) to carbon dioxide and water: CxH2x+2 + [(3x+1)/2]O2 à ¢Ã¢â‚¬  Ã¢â‚¬â„¢ xCO2 + (x+1)H2O These three reactions occur most efficiently when the catalytic converter receives exhaust from an engine running slightly above the stoichiometric point. This point is between 14.6 and 14.8 parts air to 1 part fuel, by weight, for gasoline. The ratio for LPG, natural gas and ethanol fuels is slightly different, requiring modified fuel system settings when using those fuels. Generally, engines fitted with 3-way catalytic converters are equipped with a computerized closed-loop feedback fuel injection system using one or more oxygen sensors, though early in the deployment of 3-way converters, carburetors equipped for feedback mixture control were used. While a 3-way catalyst can be used in an open-loop system, NOx reduction efficiency is low. Within a narrow fuel/air ratio band surrounding stoichiometry, conversion of all three pollutants is nearly complete. However, outside that band, conversion efficiency falls very rapidly. When there is more oxygen than required, the system is said to be running lean, and the system is in oxidizing condition. In that case, the converters two oxidizing reactions (oxidation of CO and hydrocarbons) are favoured, at the expense of the reduction of NOx. When there is excessive fuel, the engine is running rich; the reduction of NOx is favoured, at the expense of CO and HC oxidation. [edit] Oxygen storage Three-way catalytic converters can store oxygen from the exhaust gas stream, usually when the air fuel ratio goes lean.[5] When insufficient oxygen is available from the exhaust stream, the stored oxygen is released and consumed (see cerium(IV) oxide). This lean-ness occurs either when oxygen derived from NOx reduction is unavailable or certain maneuvers such as hard acceleration enrich the mixture beyond the ability of the converter to supply oxygen. [edit] Unwanted reactions Unwanted reactions can occur in the three-way catalyst, such as the formation of odiferous hydrogen sulfide and ammonia. Formation of each can be limited by modifications to the washcoat and precious metals used. It is difficult to eliminate these byproducts entirely. Sulfur-free or low-sulfur fuels eliminate or reduce hydrogen sulfide. For example, when control of hydrogen sulfide emissions is desired, nickel or manganese is added to the washcoat. Both substances act to block the adsorption of sulfur by the washcoat. Hydrogen sulfide is formed when the washcoat has adsorbed sulfur during a low temperature part of the operating cycle, which is then released during the high temperature part of the cycle and the sulfur combines with HC. [edit] For diesel engines For compression-ignition (i.e., diesel) engines, the most commonly used catalytic converter is the diesel oxidation catalyst. This catalyst uses O2 (oxygen) in the exhaust gas stream to convert CO (carbon monoxide) to CO2 (carbon dioxide) and HC (hydrocarbons) to H2O (water) and CO2. These converters often operate at 90% efficiency, virtually eliminating diesel odor and helping to reduce visible particulates (soot). But they cannot reduce NOx because chemical reactions always occur in the simplest possible way, and the existing O2 in the exhaust gas stream would react first. To reduce NOx on a compression ignition engine, the chemical composition of the exhaust must first be changed. Two main techniques are used: exhaust gas recirculation (EGR) and selective catalytic reduction (SCR). NOx trapping (with NOx absorbers) is a third method, but as of yet (2010), is not widely used. Diesel engine exhaust contains relatively high levels of particulate matter (soot), consisting in large part of elemental carbon. Catalytic converters cannot clean up elemental carbon, though they do remove up to 90% of the soluble organic fraction[citation needed], so particulates are cleaned up by a soot trap or diesel particulate filter (DPF). In the United States, all on-road heavy-duty vehicles powered by diesel and built after 1 January 2007 must be equipped with a catalytic converter and a diesel particulate filter.[6] Instead of catalysis, a reagent such as ammonia pyrolyzed in situ from urea, is sometimes used to reduce the NOx into nitrogen. One trademark product to do this is AdBlue. [edit] For lean-burn engines For lean burn spark ignition engines, an oxidation catalyst is used in the same manner as in a diesel engine. [edit] Installation Many vehicles have a pre-catalyst located close to the engines exhaust manifold. This unit heats up quickly due to its proximity to the engine, and reduces cold-engine emissions by burning off hydrocarbons from the extra-rich mixture used in a cold engine. Many three-way catalytic converters utilize an air injection tube between the first (NOx reduction) and second (HC and CO oxidation) stages of the converter. This tube is fed by a secondary air injection system. The injected air provides oxygen for the catalysts oxidizing reaction. These systems also sometimes include an upstream air injector to admit oxygen to the exhaust system before it reaches the catalytic converter. This precleans the extra-rich exhaust from a cold engine, and helps bring the catalytic converter quickly up to operating temperature. Some newer systems do not employ air injection. Instead, they provide a constantly varying mixture that quickly and continually cycles between lean and rich to keep the first catalyst (NOx reduction) from becoming oxygen loaded, and to keep the second catalyst (CO oxidization) sufficiently oxygen-saturated. They also utilize several oxygen sensors to monitor the exhaust, at least one before the catalytic converter for each bank of cylinders, and one after the converter. Some systems contain the reduction and oxidation functions separately rather than in a common housing. [edit] Damage [edit] Poisoning Catalyst poisoning occurs when the catalytic converter is exposed to exhaust containing substances that coat the working surfaces, encapsulating the catalyst so that it cannot contact and treat the exhaust. The most notable contaminant is lead, so vehicles equipped with catalytic converters can only be run on unleaded gasoline. Other common catalyst poisons include manganese primarily from the gasoline additive MMT, and silicone which can enter the exhaust stream if the engine has a leak allowing coolant into the combustion chamber. Phosphorus is another catalyst contaminant. Although phosphorus is no longer used in gasoline, it (and zinc, another low-level catalyst contaminant) was until recently widely used in engine oil antiwear additives such as ZDDP. Beginning in 2006, a rapid phaseout of ZDDP in engine oils began.[citation needed] Depending on the contaminant, catalyst poisoning can sometimes be reversed by running the engine under a very heavy load for an extended period of time. The increased exhaust temperature can sometimes liquefy or sublimate the contaminant, removing it from the catalytic surface. However, removal of lead deposits in this manner is usually not possible due to leads high boiling point. [edit] Meltdown Any condition that causes abnormally high levels of unburned hydrocarbons raw or partially-burnt fuel to reach the converter will tend to significantly elevate its temperature, bringing the risk of a meltdown of the substrate and resultant catalytic deactivation and severe exhaust restriction. Vehicles equipped with OBD-II diagnostic systems are designed to alert the driver of a misfire condition, along with other malfunctions, by means of the Check Engine light on the dashboard. [edit] Regulations This section does not citeany references or sources. Please help improve this articleby adding citations to reliable sources. Unsourced material may be challengedand removed. (March 2009) Emissions regulations vary considerably from jurisdiction to jurisdiction. In North America, most spark ignition engines of over 25 brake horsepower (19 kW) output built after January 1, 2004 are equipped with three-way catalytic converters. In Japan, a similar set of regulations came into effect January 1, 2007, while the European Union has not yet enacted analogous regulations. Most automobile spark ignition engines in North America have been fitted with catalytic converters since the mid-1970s, and the technology used in non-automotive applications is generally based on automotive technology. Regulations for diesel engines are similarly varied, with some jurisdictions focusing on NOx (nitric oxide and nitrogen dioxide) emissions and others focusing on particulate (soot) emissions. The regulatory diversity is challenging for manufacturers of the engine as it may not be economical to design an engine to meet two sets of regulations. Regulations of fuel quality vary across jurisdictions. In North America, Europe, Japan, and Hong Kong, gasoline and diesel fuel are highly regulated, and CNG and LPG are being reviewed for regulation. In most of Asia and Africa, the regulations are often lax in some places sulfur content of the fuel can reach 20,000 parts per million (2%). Any sulfur in the fuel can be oxidized to SO2 (sulfur dioxide) or even SO3 (sulfur trioxide) in the combustion chamber. If sulfur passes over a catalyst, it may be further oxidized in the catalyst, i.e. (SO2 may be further oxidized to SO3). Sulfur oxides are precursors to sulfuric acid, a major component of acid rain. While it is possible to add substances like vanadium to the catalyst wash coat to combat sulfur oxide formation, such addition will reduce the effectiveness of the catalyst. The most effective solution is to further refine fuel at the refinery to produce ultra-low sulfur diesel. Regulations in Japan, Europe, and North America tightly restrict the amount of sulfur permitted in motor fuels. However, the expense of producing such clean fuel make it impractical for use in many developing countries. As a result, cities in these countries with high levels of vehicular traffic suffer from acid rain, which damages stone and woodwork of buildings and damages local ecosystems. [edit] Negative aspects Some early converter designs greatly restricted the flow of exhaust, which negatively affected vehicle performance, driveability, and fuel economy.[7] Because they were used with carburetors incapable of precise fuel/air mixture control, they could overheat and set fire to flammable materials under the car.[8] Removing a modern catalytic converter in new condition will only slightly increase vehicle performance without retuning,[9] but their removal or gutting continues.[7]HYPERLINK http://en.wikipedia.org/wiki/Catalytic_converter#cite_note-9[10] The exhaust section where the converter was may be replaced with a welded-in section of straight pipe, or a flanged section of test pipe legal for off-road use that can then be replaced with a similarly fitted converter-choked section for legal on-road use, or emissions testing.[9] In the US and many other jurisdictions, it is illegal to remove or disable a catalytic converter for any reason other than its immediate replacement[citation need ed]; vehicles without functioning catalytic converters generally fail emission inspections. The aftermarket supplies high-flow converters for vehicles with upgraded engines, or whose owners prefer an exhaust system with larger-than-stock capacity.[11] [edit] Warm-up period Most of the pollution put out by a car occurs during the first five minutes before the catalytic converter has warmed up sufficiently.[12] [edit] Environmental impact Catalytic converters have proven to be reliable and effective in reducing noxious tailpipe emissions. However, they may have some adverse environmental impacts in use: The requirement for a rich burn engine to run at the stoichiometric point means it uses more fuel than a lean burn engine running at a mixture of 20:1 or less. This increases the amount of fossil fuel consumed and the carbon dioxide emissions of the vehicle. However, NOx control on lean burn engines is problematic. Although catalytic converters are effective at removing hydrocarbons and other harmful emissions, they do not solve the fundamental problem created by burning a fossil fuel. In addition to water, the main combustion product in exhaust gas leaving the engine through a catalytic converter or not is carbon dioxide (CO2).[13] Carbon dioxide produced from fossil fuels is one of the greenhouse gases indicated by the Intergovernmental Panel on Climate Change (IPCC) to be a most likely cause of global warming.[14] Additionally, the U.S. Environmental Protection Agency (EPA) has stated catalytic converters are a significant and growing cause of global warming, due to their release of nitrous oxide (N2O), a greenhouse gas over 300 times more potent than carbon dioxide.[15] Catalytic converter production requires palladium or platinum; part of the world supply of these precious metals is produced near the Russian city of Norilsk, where the industry (among others) has caused Norilsk to be added to Time Magazines list of most polluted places.[16] [edit] Theft Due to the external location and the use of valuable precious metals including platinum, palladium, and rhodium, converters are a target for thieves. The problem is especially common among late-model Toyota trucks and SUVs, due to their high ground clearance and easily-removed bolt-on catalytic converters. Welded-in converters are also at risk of theft from SUVs and trucks, as they can be easily removed.[17]HYPERLINK http://en.wikipedia.org/wiki/Catalytic_converter#cite_note-17[18] Theft removal of the converter can often inadvertently damage the cars wiring or fuel line resulting in dangerous consequences. Rises in metal costs in the United States during recent years have led to a large increase in theft incidents of the converter,[19] which can then cost as much as $1000 to replace.[20] [edit] Diagnostics Various jurisdictions now legislate on-board diagnostics to monitor the function and condition of the emissions control system, including the catalytic converter. On-board diagnostic systems take several forms. [edit] Temperature sensors Temperature sensors are used for two purposes. The first is as a warning system, typically on 2-Way catalytic converters such as are still sometimes used on LPG forklifts. The function of the sensor is to warn of catalytic converter temperature above the safe limit of 750  °C (1,380  °F). More recent catalytic converter designs are not as susceptible to temperature damage and can withstand sustained temperatures of 900  °C (1,650  °F).[citation needed] Temperature sensors are also used to monitor catalyst functioning usually two sensors will be fitted, with one before the catalyst and one after to monitor the temperature rise over the catalytic converter core. For every 1% of CO in the exhaust gas stream the exhaust gas temperature will rise by 100 °C.[citation needed] [edit] Oxygen sensors The Oxygen sensor is the basis of the closed loop control system on a spark ignited rich burn engine, however it is also used for diagnostics. In vehicles with OBD II, a second oxygen sensor is fitted after the catalytic converter to monitor the O2 levels. The on-board computer makes comparisons between the readings of the two sensors. If both sensors give the same output, the computer recognizes the catalytic converter is not functioning or removed, and will operate a check engine light and retard engine performance. Simple oxygen sensor simulators have been developed to circumvent this problem by simulating the change across the catalytic converter with plans and pre-assembled devices available on the internet, though these are not legal for on-road use.[21] Similar devices apply an offset to the sensor signals, allowing the engine to run a more fuel economical lean burn that may however damage the engine or the catalytic converter.[22] [edit] NOx sensors NOx sensors are extremely expensive and are generally only used when a compression ignition engine is fitted with a selective catalytic reduction (SCR) converter, or a NOx absorber catalyst in a feedback system. When fitted to an SCR system, there may be one or two sensors. When one sensor is fitted it will be pre-catalyst, when two are fitted the second one will be post catalyst. They are utilized for the same reasons and in the same manner as an oxygen sensor the only difference is the substance being monitored.

NAACP Essay -- essays research papers

NAACP The civil rights movement in the United States has been a long, primarily nonviolent struggle to bring full civil rights and equality under the law to all Americans. It has been made up of many movements, though it is often used to refer to the struggles between 1945 and 1970 to end discrimination against African-Americans and to end racial segregation, especially in the U.S. South. It focuses on that particular struggle, rather than the comparable movements to end discrimination against other ethnic groups within the United States or those struggles, such as the women's liberation, gay liberation, and disabled rights movements, that have used similar tactics in pursuit of similar goals. The civil rights movement has had a lasting impact on United States society, both in its tactics and in increased social and legal acceptance of civil rights. One of the most important organizations of this era was the NAACP (National Association for the Advancement of Colored People). NAACP is an or ganization composed mainly of American blacks, but with many white members, whose goal is the end of racial discrimination and segregation. The association was formed as the direct result of the lynching (1908) of two blacks in Springfield, Ill. The incident produced a wide response by white Northerners to a call by Mary W. Ovington, a white woman, for a conference to discuss ways of achieving political and social equality for blacks. This conference led to the formation (1910) of the NAACP, headed by eight prominent Americans, seven white and one, William E. B. Du Bois, black (wikipedia 1). The selection of Du Bois was significant, for he was a black who had rejected the policy of gradualism advocated by Booker T. Washington and demanded immediate equality for blacks. From 1910 to 1934 Du Bois was the editor of the association's periodical The Crisis, which reported on race relations around the world. The new organization grew so rapidly that by 1915 it was able to organize a partially successful boycott of the motion picture The Birth of a Nation, which portrayed blacks of the Reconstruction era in a distorted light( S partacus 2). Most of the NAACP's early efforts were directed against lynching. In this area it could claim considerable success. In 1911 there were 71 lynchings in the United States, with a black person the victim 63 times; by the 1950s lynching had virtua... ...erica's darker citizens were denied. From the ballot box to the classroom, the dedicated workers, organizers, and leaders who forged this great organization and maintain its status as a champion of social justice, fought long and hard to ensure that the voices of African Americans would be heard. The legacy of those pioneers such as W.E.B DuBois, Thurgood Marshall and Roy Wilkens and the hundreds of thousands of nameless faces who worked tirelessly cannot and must not be forgotten (NAACP 1). The history of the NAACP is one of blood sweat and tears. From bold investigations of mob brutality, protests of mass murders, segregation and discrimination, to testimony before congressional committees on the vicious tactics used to bar African Americans from the ballot box, it was the talent and tenacity of NAACP members that saved lives and changed many negative aspects of American society. While much of its history is chronicled in books, articles, pamphlets and magazines, the true movement lies in the faces---black, white, yellow, red, and brown---united to awaken the conscientiousness of people, and a nation. Work Cited www.en.wikipedia.org www.naacp.org www.spartacus.schoolnet.co

Common Law Essay

a)Â  In a letter dated 14/02/2011, the manager (Dave) of Excellent Foods (EF) outlined conditions in writing to the manager (Ben) of Safe Foods (SF) in relation to the purchase of EF. These conditions were that SF must pay the valued amount of EF, which totaled $120,000, $30,000 more than the original amount that SF had been prepared to pay and stipulated during earlier negotiations. At the time of the earlier negotiations, SF also had set a purchase requirement, which was that EF’s sales must increase by 20% over the next two months and if this requirement was met, SF would be prepared to pay the $90,000. After earlier negotiations, EF had their business valued at $120,000 and notified SF of the valuation and that they now required this amount, not the $90,000 that SF had offered. SF did not reply to EF. Whilst EF met the sales increase target and forwarded the record of sales to SF along with the transfer of business contract as well as a new condition of the contract being that EF require 10% of the 120,000 within 14 days, SF responded in writing stating they no longer were interested in purchasing EF. It would appear that EF are no longer interested in purchasing SF due to the $30,000 price increase and the term that they would now need to pay 10% within 14 days. An important aspect in forming a legally binding contract is giving and receiving the acceptance of an offer. The requirement of acceptance with every binding legal contact is tied closely to the concept of unqualified mutual assent. Only when both parties have given their mutual consent does the law consider a binding legal contact to have been formed. Hence, if the offeree remains silent, their silence cannot constitute an acceptance.[1] Another important aspect when creating a legally binding contract is that the acceptance of the offer must exactly mirror the terms and conditions of the offeree and vice versa. If there is even a slight difference, this will most likely not constitute a valid acceptance. If an offer is made that does not mirror the terms of the original offer, than this is considered a counter-offer, which now negates the original offer. An example of this is demonstrated in the case of Hyde v Wrench (1840) where Wrench offers to sell his land to Hyde for the price of 1200 pounds of which Hyde declined to accept. Wrench responded with a counter-offer of 1000 pounds and Hyde responded with another counter-offer of 950 pounds. When Wrench declined the counter offer, Hyde decided he would accept the earlier offer of 1000 pounds, however Wrench decided he would no longer sell his land to Hyde for this amount. As Hyde had made another counter-offer after the earlier offer, the offer of 1000 pounds was now destroyed. Hyde sued Wrench for breach of contract claiming that the earlier offer was not withdrawn however the court found that Wrench did not need to withdraw the offer of 1000 pounds as it was destroyed when the counter-offer of 950 pounds was made.[2] In this case, SF made an offer to EF, being $90,000 if sales increase by 20% in two months. EF later responded with a counter-offer of $120,000, which then destroyed the earlier offer of $90,000. SF did not respond to this counter offer, therefore not accepting the new offer. EF also added terms to the offer that were not previously discussed with SF, which also did not mirror the terms of the earlier offer of which the court considers being a strict requirement for full and unequivocal assent.[3] Excellent Foods cannot commence an action for breach of contract against Safe Foods as the counter-offer negates the original offer of which Safe Foods did not respond to and therefore is not considered as an acceptance of the terms. b)Â  Promissory estoppel is an equitable action, which is designed to enforce promises made from one party to another where the promises are not supported by consideration. The doctrine of promissory estoppel can only be applied if a clear promise was made from the promisor to the promisee, if the promisse has suffered a significant loss from the promiser now going back on its promise, if the promiser acted unconscionably, and if the promisse undertook certain acts (or refrained from undertaking certain acts) due to the promiser’s initial promise. A leading case which illustrates the purpose of promisary estoppal is Waltons Stores v Maher where Waltons negotiated with Maher over the grant of a lease of property that Maher owned. Maher agreed to demolish a building in order to make way for a new custom designed building to be occupied by Waltons. Changes and agreements were made by both parties over the following months. Waltons later decided that they no longer required the building after Maher had already informed then that they were proceeding with the demolition and despite being aware of this, advised their solicitors to ‘go slow’ in informing Maher of their reservations. Due to Maher having initially received a clear promise, suffered considerable loss and completed many acts under the belief that Waltons would go ahead with the promise as well as Waltons acting unconscionably against Maher in ‘going slow’ in informing Maher of their true intentions, Maher was able to rely on promisary estoppel and therefore won on first instance and later at the appeal.[4] In this case, Excellent Foods did not suffer any considerable loss from Safe Foods not following through with the business transfer. Whilst there was an initial promise made by SF to EF, EF later requested 10% of the transfer price of $120,000 within 14 days– a term that had not previously been negotiated. It may be because of this term that SF does not wish to continue with the transfer in which case they have not acted unconscionably. EF informed SF in writing that they did not wish to continue with the transfer.

Whether Taxation Is The Most Effective Solution To Market Failures

?Discuss whether taxation is the most effective solution to market failures arising from negative externalities Market failure is when the free market fails to provide an efficient allocation of resources. Negative externalities are the costs to a third party of a particular action, and it is where the social cost is greater than the private cost. Taxation is a solution to correct market failure which is arising from negative externalities. Introducing an indirect tax, (a tax levied on goods and services), can generate a reduction in consumption of the good which produce the negative externalities.An indirect tax can internalise the cost of the negative externality by discouraging its production. The government places a tax on producers, which will increase their costs of production. This can be shown in a diagram. The increase in costs of production will reduce supply and therefore shift the supply curve in from S to S1 which results in an increase in price from P to P1 and a decrea se in quantity from Q to Q1. The tax is indicated on the graph as the difference between S and S1. However, the effectiveness of this tax depends on the price elasticity of demand for the product.If the PED is inelastic, consumers will be unresponsive to a change in price, so producers may pass on most of the tax burden to consumers, who will continue to buy the product. The tax set by the government must be equal to the size of the external costs associated with the product, and this is difficult to set especially if the effect is not quantifiable. If the tax was set too low, it would be ineffective, and if it was set too high, the consumers may stop purchasing it altogether, which may have other undesirable outcomes. The amount of tax paid by the consumer is shown by area A, and the amount paid by producers is shown by area B.Ideally, producers should bear the full cost of the tax, but goods with inelastic demand may mean that they shift this on to consumers. Where consumers pay m ore, this is a situation where taxation is ineffective at reducing market failure as it has not reduced consumption of goods causing negative externalities. A reason why indirect taxation may be effective in correcting market failure is that the policy will generate revenue for the government. The revenue collected will be greater if the tax is set on inelastic goods because this means that consumers will pay for them regardless of an increase in price.Also, the revenue gathered from the tax can be used to fund schemes to reduce consumption of the product, for example, educating the younger people on the negative effects of an action. The revenue could also be used to correct the market failure by minimising the effect on the third parties. Another way of dealing with negative externalities is government legislation to correct the market failure. Placing restrictions on demerit goods, (their consumption is more harmful than realised), can help to reduce market failure as it is their use that often leads to negative externalities arising.Legislation can be effective, but it takes a long time to enforce and can also be costly. Overall, introduction of an indirect tax can reduce market failure which arises from negative externalities. The reduction in supply that results from the tax increases the price and decreases the quantity, which causes a shift along the demand curve. This increase in price may deter consumers from purchasing the good. However, it is difficult to set the correct amount of tax on the good, because often, the negative effects are not quantifiable, and their value must be judged.It is important that the level of tax is just right, because if it is set too low, it will be ineffective, and if set too high, consumers may completely stop purchasing it, which may have other undesirable effects. The producer must pay the greater proportion of the tax, but if the demand for the product is inelastic, they may shift this on to consumers, who will pay for it regardless of the price. On its own, taxation may not be the most effective way of correcting market failure arising from negative externalities, but together with legislation, may provide to be more effective..