专业课资料 练习题 真题 北京大学经济研究中心经济学原理双学位 Prolems Set I

Principles of Economics, Class 2Problem Set I(Due on Oct 16, 2010)Note: you are required to: 1) answer questions on A4 papers, with your Name and Student ID No. on the first page; 2) complete it independently; 3) hand in your solutions before 10:00 p.m. on Oct. 16, 2010.You can answer either in English or in Chinese.Part I Multiple Choice (40 points).Identify the choice that best completes the statement or answers the question.1. If an economy is operating at a point inside the production possibilities curve, a.its resources are being wasted.b.the curve will begin to shift inward.c.the curve will begin to shift outward.d.This is a trick question because an economy cannot produce at a point inside the curve.2. Which of the following would most likely increase the demand for peanut butter? a.a decrease in the price of bread, a good that is often used with peanut butterb.a discovery that the average daily consumption of peanut butter decreases ones life span by 15 yearsc.crop failures that raise the price of peanutsd.a decrease in the price of all substitute protein products3. The price of chicken increases as the result of higher pork prices. This indicates thata.chicken and pork are substitutes.b.chicken and pork are complements.c.the market demand for pork is inelastic.d.the market demand for chicken is elastic.4. The law of demand refers to a.the decrease in price that can be expected as more units of a product are demanded.b.the increase in price that results from an increase in demand for a good of limited supply.c.the inverse relationship between the price of a good and the quantity demanded.d.the increase in the quantity of a good available when its price increases.5. The price of a good will tend to fall a.when there is excess demand for the good.b.when there is excess supply of the good.c.when demand for the good increases and producers attempt to maintain their profits.d.when the supply of the good decreases.6. Use the table below to choose the correct answer. The table is a schedule of the supply and demand for coffee.Quantity DemandedQuantity SuppliedPrice per Pound(monthly)(monthly)$0.50160$1.00101$2.0072$4.0044$6.0035$8.0017$10.00010The equilibrium market price of coffee would be a.$2 per pound.b.$4 per pound.c.$6 per pound.d.$8 per pound.7.Which of the following is most likely to cause a shift in the demand curve to the right? a.Consumers income declines.b.The price of substitute goods increases.c.The cost of resources used to produce a product declines.d. The price of the product decreases.8. A simultaneous increase in both supply and demand will: a.increase the equilibrium price.b.decrease the equilibrium price.c.increase the equilibrium quantity.d.decrease the equilibrium quantity.9. If you are willing to pay RMB 20 for a cup of ice-cream but you only have to pay RMB 15, the RMB 5 difference is:a.your consumer surplus. b.the producers deficit.c.your consumer deficit.d.the producers surplus.10.Consider the demand curve. If price is 4, the elasticity of demand is: a.-1b.-2c.-0.5d.-0.0511. Consider the demand curve . If the value of r rises, the demand curve will:a.shift to the right. b.shift to the left.c.remain unchanged.d.rotate along the quantity axis.12. A tax on sales of a good, when compared to the market equilibrium without the tax, will result in a_ price paid by buyers and a _ quantity traded.a. higher; lowerb. lower; lowerc. higher; higherd. lower; higher13. Which of the following best explains the source of consumer surplus for good A?a. Many consumers would be willing to pay more than the market price for good A.b. Many consumers pay prices that are greater than the equilibrium price of good A.c. Many consumers think the market price of good A is greater than its cost.d. Many consumers think the price elasticity of demand for good A is unit elastic.14. Consider all the demand and supply curves which traverse at a certain point. Consumer surplus tends to be smaller whena. demand is elastic.b. supply is elastic.c. demand is inelastic.d. supply is inelastic.15. The condition is the same with Q14. Producer surplus tends to be larger whena. supply is elastic.b. demand is elastic.c. supply is inelastic.d. demand is inelastic.16. Doreen has preferences represented by the utility function U(x, y) = 20x+ 8y. She consumes 11 units of good x and 5 units of good y. If her consumption of good x is lowered to 1, how many units of y must she have in order to be exactly as well as before?a. 30 units of good yb. 27 units of good yc. 24 units of good yd. 18 units of good y17. The cost to Air China of letting its employees fly at no charge a. is zero. b. will depend on the value employees place upon travel. c. is greater during the Spring Festival than at most other times. d. depends on the alternatives open to the employees.18. Chinas Ministry of Railway is trying to decide whether or not to run an additional train into Tianjin from Beijing at 8:15 a.m. The total cost of running trains between 8:00 a.m. and 9:00 a.m. is RMB45,000 and the expected revenues on any given day are RMB100,000 during this time period. The cost of running the additional train is RMB4,000 and it is expected that revenues will rise to RMB103,500. The Ministry of Railway should a. run the train because the total revenues are greater than the total costs. b. run the train because the firms revenues will rise. c. not run the train because the total costs are already too high. d. not run the train because the marginal cost of RMB4000 is greater than the marginal revenue of RMB3,500.Figure 0119. Which of the following would most likely cause the production possibilities curve for breadfruit and fish to shift from AA to BB in the above figure (Figure 01)? a.an increase in the labor forceb.choosing more fish and less breadfruitc.choosing more breadfruit and fewer fishd.a decrease in the capital stock20. Which of the following are the best examples of substitute goods? a. personal computers and computer software programs b. milk and cookies c. IBM and Gateway personal computers d. hot dogs and mustard21. Which of the following sets of goods are most likely to be complementary goods? a. shoes and pizza b. automobiles and computers c. baseballs and baseball gloves d. football tickets and baseball tickets22. Consider a market in equilibrium. Firms who advertise in this market are attempting to shift the a. supply curve to the right. b. supply curve to the left. c. demand curve to the left. d. demand curve to the right.23. When a market is in equilibrium, a. quantity demanded will equal quantity supplied. b. a shortage will be present. c. a surplus will be present. d. sellers will continue to expand production to increase revenues. 24. A price ceiling might be an appropriate government response to a a. period of falling farm prices due to unusually good harvests. b. substantial increase in farm productivity due to applications of new technology in agriculture. c. national security crisis leading to major shortages of essential goods. d. period of extraordinary large surpluses of farm goods. 25. If price elasticity of demand is 2.0, this implies that consumers would a. buy twice as much of the good if price falls by 10 percent. b. require a 2 percent cut in price to raise quantity demanded of the good by 1 percent. c. buy 2 percent more of the good in response to a 1 percent cut in price. d. require at least a $2 increase in price before showing any response to the price increase.26. If Jack Jones T-shirt lowers its price from RMB 60 to RMB 50 and finds that students increase their quantity demanded from 400 to 600 T-shirts, then the demand for Jack Jones T-shirts within this price range is a. price inelastic. b. price elastic. c. unit elastic. d. cross elastic.27. A government seeking to raise revenue would be most likely to tax a good with a a. high income elasticity of demand. b. low cross-price demand elasticity. c. high price elasticity of demand.d. low price elasticity of demand.28. Temporary shortages in a market are eliminated by a. decreases in the price, which cause quantity supplied to fall and quantity demanded to rise. b. decreases in the price, which cause quantity supplied to rise and quantity demanded to fall. c. increases in the price, which cause quantity supplied to fall and quantity demanded to rise. d. increases in the price, which cause quantity supplied to rise and quantity demanded to fall. 29. Which of the following is a factor held constant when deriving a supply curve for pork? a.the price of pig.b.the price of pork.c.the wages of workers who raise pigs.d.both a and c are hold constant.30. Compared to sellers, consumers will pay more of the burden of a tax if: a.demand is more elastic than supply.b.supply is more elastic than demand.c.the tax is higher.d.the tax is lower.31. Charlies indifference curves have the equation Xb=constant/Xa; where larger constants denote better indifference curves. Thus Charlie strictly prefers the bundle (9, 19) to the bundle:a. (19, 9).b. (10, 18).c. (12, 14).d. more than one of these bundles.32. Preferences are said to be monotonic if:a. all goods must be consumed in fixed proportions.b. all goods are perfect substitutes.c. more is always preferred to less.d. there is diminishing marginal rate of substitution.33. If two goods are perfect complements:a. there is a bliss point and the indifference curves surround this point.b. consumers will only buy the cheaper of the two goods.c. indifference curves have right angle.d. None of the above.34. Mary Granola consumes oranges and apples. Marys indifference curves are kinky. When she is consuming more oranges than apples, she is just willing to trade 5 oranges for 1 apples. When she is consuming more apples than oranges, she is just willing to trade 2 apples for 1 oranges. Let P1 be the price of apples and P2 the price of oranges. Mary maximizes her utility subject to her budget constraint. Which is true? (Hint: Sketch one of her indifference curves.)a. When P1 P2; she must consume only oranges.b. When P1 P2; she must consume 5 times as many oranges as apples.c. When P1 5P2; she must consume only oranges.d. When 2P1 P2; she must consume only apples.35. Coke and Pepsi are perfect substitutes for Mr. Drinker and the slope of his indifference curves is minus 1. One day he bought 2 cans of Coke and 20 cans of Pepsi. (The cans of both drinks are the same size.)a. Mr. Drinker prefers Pepsi to Coke.b. Coke and Pepsi cost the same.c. Coke is less expensive than Pepsi.d. Coke is more expensive than Pepsi.36. This weekend, Martha has time to read 40 pages of economics and 30 pages of sociology. Alternatively, she could read 20 pages of economics and 70 pages of sociology. Which of these equations describes all combinations of pages of economics, E; and sociology, S; that she could read over the weekend?a. E + S =70b. E+2S =100c. E + S =90d. 2E + S = 11037. If she spends her entire budget, Heidi can afford 39 peaches and 12 pears. She can also just afford 24 peaches and 17 pears. The price of peaches is 9 cents. What is the price of pears in cents?a. 37b. 3c. 12d. 2738. Macs utility function is U(x, y)= max2x-y,2y-x.a. Goods x and y are perfect substitutes.b. If Mac has more x than y; a small increase in his consumption of y would lower his utility.c. If Mac has more y than x; a small decrease in his consumption of y would raise his utility.d. Mac always prefers more of each good to less.39. Oswald Odd consumes only goods 1 and 2. His utility function is U(x1,x2)= x1 + x2 + minx1,x2. Each of Oswalds indifference curves is:a. L-shaped.b. made up of 3 line segments with slopes -2, -1 and -1/2.c. made up of two line segments with slopes -2 and -1/2.d. is smooth and has no kinks.40. The basic difference between macroeconomics and microeconomics is that a.macroeconomics is concerned with the forest (aggregate markets), while microeconomics is concerned with the individual trees (subcomponents).b.macroeconomics is concerned with policy decisions, while microeconomics applies only to theory.c.microeconomics is concerned with the forest (aggregate markets), while macroeconomics is concerned with the trees (subcomponents).d. opportunity cost is applicable to macroeconomics, and the fallacy of composition relates to microeconomics.Part II Calculation.You are required to provide detailed steps.1. (12 points) Tom is stranded on a desert island and can either sh or harvest dates. Six points on his production possibilities frontier are given in table below. Dates gatheredFish caughtA450B361C272D183E94F05a. (2 points) Plot these possibilities on a “Dates gathered /Fish caught” grid, label the points, and draw the PPF. Put Dates gathered on the vertical axis. PPF is short for Production Probabilities Frontier.b. (2 points) If Tom moves from possibility C to D, what is the opportunity cost per sh? If he moves from D to C, what is the opportunity cost of dates? c. (2+2 points) In general, what happens to the opportunity cost of a sh as more sh are caught? What about the opportunity cost of dates as more dates are harvested? d. (2+2 points) Based on the original PPF you plotted, is a combination of 40 dates and 1 sh attainable? Is this combination an efficient one? Explain. 2. (30 points) Mr. Pizza sells small pieces of pizza. Here we assume that the price of pizza is determined by the market.Price of Pizza（RMB/piece）demand(piece)supply(piece)142002280100317012041401405120170a. (2+2 points) Plot the demand curve and supply curve using the chart on the right.b. (2+2 points) What is the equilibrium price and quantity of pizza?c. (2+2 points) What are the consumer surplus and the producer surplus when the market is clear? Explain it on the graph.d. (2+2+4 points) Suppose the government decides to impose a tax on food now. How will the equilibrium price and quantity change? Furthermore, describe the change of the social welfare. Please also show these changes on the graph. e. (4 points) Government could make a choice: tax on income, or tax on specific consumption. Discuss the benefit and disadvantage of imposing consumption tax. f.