Microeconomics课程试卷A.doc

Microeconomics课程试卷A一、选择题：（共15小题，每小题2分，共30分）1. A Giffen good: A. has an upward-sloping demand curve.B. has a downward-sloping demand curve.C. has a horizontal demand curve.D. has a vertical demand curve.2. The consumer optimum occurs at:A. any point of intersection between the budget line and anindifference curve.B. a point of tangency between the budget line and an indifferencecurve.C. the point where the slope of the indifference curve equalsthe ratio of the quantities.D. a point where the budget line cuts the curve from below.3. The slope of the budget constraint line is equal to:A. the ratio of marginal utilities.B. the ratio of money income to the price of the good on thehorizontal axis.C. the ratio of money income to the price of the good on thevertical axis.D. the relative price of the two goodsthe price of one goodcompared with the price of the other.4.Assume the demand curve for compact discs slopes downwards,and the supply curve slopes upwards. If the price of CD playersdecreases, then:A. the equilibrium price of compact discs will fallB. the equilibrium price of compact discs will riseC. the equilibrium price of compact discs will stay the sameD. None of the above are correct5. Implicit costs are:A. the payments made to labour only.B. the payments made by the firm to others.C. the opportunity cost of resources owned by the firm.D. the same as accounting profit.6. When a firms cost curves exhibit economies of scale:A. the long-run average cost curve is horizontal.B. the long-run average cost curve is downward-sloping.C. the long-run average cost curve is upward-sloping.D. the long-run average cost equals the short-run average costfor all levels of output.7. Economic profits for perfectly competitive firms: A. will continue in the long run for a few efficient firms.B. will shift the industry demand function rightward.C. will attract new firms into the industry in the long run.D. will result in an increase in long-run equilibrium price.8.If the demand for milk increases when the price of pickles increases(ceteris paribus), then milk and pickles are (A) normal goods. (B) inferior goods.(C) substitutes in consumption. (D) complements in consumption.9.The quantity that a firm is willing and able to produce and make available for sale at each possible price (in a series of prices) is represented by the (A) demand curve. (B) supply curve.(C) marginal product curve. (D) production possibilities curve10.If the quantity demanded of bananas increases by 10% when its pricedecreases by 25%, then the price elasticity of banana demand, Ed, is (A) 0.15. (B) 0.35. (C) 0.4. (D) 1.25.11. The demand for a good will be more elastic the (A). More the good is considered a luxury.(B). More narrowly defined the market (e.g. hamburger versus beef).(C). The longer the time period being considered.(D). All of the above12. A government-imposed maximum price at which a good or service canbe sold is called a price (A). Ceiling (B). Floor (C). Equilibrium (D). Support13.If, at a given quantity of labor, MPL is greater than APL, then (A) APL is increasing. (B) APL is decreasing.(C) TPL is at a maximum. (D) APL is at a maximum.14. Which of the following industries is closest to perfectcompetition? A. steel B. auto C. wheat D. aluminum 15. An oligopolistic market (A) has a small number of rival firms, and each is large relative to the market.(B) makes the demand for each firm independent of the actions of its rivals.(C) has low entry barriers facing firms that could otherwise enter themarket.(D) is all of the above.二、判断题：（共10小题，每小题1分，共10分）1. According to the Law of Demand, a decrease in the price of sodaincreases the demand demanded for soda. 2. If beer is an inferior good for a consumer named Fred, then (ceterisparibus) a decrease in Freds income decreases his demand for beer. 3. If coffee and tea are substitutes in consumption, then an increase in the price of tea decreases both the quantity demanded and the supply of coffee. 4. If cheese demand is relatively inelastic, then an increase in the supply of cheese will increase the income (total revenue) of cheese producers. 5 In the long run all costs can vary.6 If average fixed cost is $50 at an output of 20 units, it would decline to $25 if output were increased to 40 units. 7. A perfectly competitive firm faces a downward-sloping, relativelyelastic demand curve . 8. A perfectly competitive firms SR supply curve is given by the firmsMC curve for market prices above the minimum of the AVC curve. 9. A perfectly competitive industry is in LR equilibrium when every firmproduces at its profit maximizing output level.10. Monopolists can control the price. 三、名词解释（共5小题，每小题3分，共15分）1.Scarcity 2 Total Revenue 3.Marginal Cost4.Consumer surplus 5 A monopoly 四、简述题（共2小题，每题9分，共18分）1. What is Indifference Curve? What are the Properties of Indifference Curve? 2 A subsidy is the opposite of a tax. With a $0.50 tax on the buyers of ice-cream cones, the government collects $0.50 for each cone purchased; with a $0.50 subsidy for the buyers of ice-cream cones, the government pays buyers $0.50 for each cone purchased.a. Show the effect of a $0.50 per cone subsidy on the demand curve for ice-cream cones, the effective price paid by consumers, the effective price received by sellers, and the quantity of cones sold. b. Do consumers gain or lose from this policy? Do producers gain or lose? Does the government gain or lose?五、计算题（共3小题，每小题9分，共27分）1. Suppose that business travelers and vacationers have the following demand for airline tickets from New York to Boston:PRICEQUANTITY DEMANDED(BUSINESS TRAVELERS)QUANTITY DEMANDED(VACATIONERS)$1502,1001,0002002,0008002501,9006003001,800400a. As the price of tickets rises from $200 to $250, what is the price elasticity of demand for (i) business travelers and (ii) vacationers? (Use the midpoint method in your calculations.)b. Why might vacationers have a different elasticity than business travelers?2 Suppose a firm has got such short run cost functioin: TC(Q)=Q3-10Q2+17Q+66.(1) Is the firms production in the short run or long run? why?(2) What is TVC(Q)? (3) What is AVC(Q)? (4) What is AFC(Q)? (5) What is MC(Q)?3. Consider total cost and total revenue given in the table below: QUANTITY01234567Total cost$8$9$10$11$13$19$27$37Total revenue08162432404856a. Calculate profit for each quantity. How much should the firm produce to maximize profit?b. Calculate marginal revenue and marginal cost for each quantity. Graph them. (Hint: Put the points between whole numbers. For example, the marginal cost between 2 and 3 should be graphed at 2 1/2.) At what quantity do these curves cross? How does this relate to your answer to part (a)?c. Can you tell whether this firm is in a competitive industry? If so, can you tell whether the industry is in a long-run equilibrium? 江西农业大学Microeconomics试卷A答案(本试题要求考生尽量用英文回答；如部分考生由于英语水平有限，有的题目用中文答题，也可酌情给分)一、选择题：（共15小题，每小题2分，共30分）1.A 2.B 3.D 4.B 5.C 6.B 7.C 8.C 9.B 10.C 11.D 12.A 13.A 14.C 15.A 二、判断对错：（共10小题，每小题1分，共10分）1.T 2.F 3.F 4.T 5.T 6.T 7.F 8.T 9.F 10.T 三、名词解释（共5小题，每小题3分，共15分）1.Scarcity: means that society has less resources to offer thanpeople wish to have.2 Total Revenue: The sum of the payments that the firm receives from thesale of its output.3.Marginal Cost: MC is the change in total cost due to the production ofone more unit of output4.Consumer surplus:The difference between what a consumer is willing topay and what she has to pay.5.A monopoly is the sole seller of its product and its product does nothave close substitutes.四、简述题（共2小题，每题9分，共18分）1. What is Indifference Curve? What are the Properties of Indifference Curve? An indifference curve depicts bundles of goods that leave the consumer equally well-off. It shows the combinations of goods that give the consumer a constant level of utility.(1)Higher indifference curves are preferred to lower ones. (The further from the origin, the higher the utility)(2)Indifference curves are downward sloping. (Negatively sloped-slope is MRS)(3)Indifference curves do not cross. (Cannot intersect)(4)Indifference curves are bowed inward. (Convex shaped -diminishing MRS)2 A subsidy is the opposite of a tax. With a $0.50 tax onthe buyers of ice-cream cones, the government collects $0.50 for each cone purchased; with a $0.50 subsidy forthe buyers of ice-cream cones, the government pays buyers $0.50 for each cone purchased.a. Show the effect of a $0.50 per cone subsidy on the demand curve for ice-cream cones, the effective price paid by consumers, the effective price received by sellers, and the quantity of cones sold. b. Do consumers gain or lose from this policy? Do producers gain or lose? Does the government gain or lose?a.The effect of a $0.50 per cone subsidy is to shift the demand curve up by $0.50 at each quantity, since at each quantity a consumers willingness to pay is $0.50 higher. The effects of such a subsidy are shown in Figure 14. Before the subsidy, the price is P1. After the subsidy, the price received by sellers is PS and the effective price paid by consumers is PD, which equals PS minus 50 cents. Before the subsidy, the quantity of cones sold is Q1; after the subsidy the quantity increases to Q2.b.Because of the subsidy, consumers are better off, since they consume more at a lower price. Producers are also better off, since they sell more at a higher price. The government loses, since it has to pay for the subsidy. 五、计算题（共3小题，每小题9分，共27分）1. a.For business travelers, the price elasticity of demand when the price of tickets rises from $200 to $250 is (2,000 - 1,900)/1,950/(250 - 200)/225 = 0.05/0.22 = 0.23. For vacationers, the price elasticity of demand when the price of tickets rises from $200 to $250 is (800 - 600)/700 / (250 - 200)/225 = 0.29/0.22 = 1.32.b.The price elasticity of deman