課程名稱︰經濟學原理與實習
課程性質︰必修
課程教師︰張清溪
開課學院：社會科學院
開課系所︰經濟系
考試日期（年月日）︰99/11/08
考試時限（分鐘）：60
是否需發放獎勵金：是
（如未明確表示，則不予發放）
一、選擇題(50%，每題5分)
1. For which of the following goods would demand be mast inelastic?
a.white chocolate
b.Godiva chocolate
c.chocolate
d.All three would have the same slasticity of demand since they are
all related.
2. Jean-Paul says that he will spend exactly 75 cents a day on M&Ms,
regardless of the price of M&Ms. Jean-Paul’s demand for M&Ms is
a.perfectly elastic.
b.unit elastic.
c.perfectly inelastic.
d.None of the above answers is correct.
3. Last month, sellers of good Y took in $100 in total revenue on sales of
50 units of good Y. This month sellers of good Y raised their price and took
in $120 in total revenue on sales of 40 units of good Y. At the same time,
the price of good X stayed the same, but sales of good X increased from 20
units to 40 units. We can conclude that goods X and Y are
a.substitutes, and have a cross-price elasticity of 0.60.
b.complements, and have a cross-price elasticity of 0.60.
c.substitutes, and have a cross-price elasticity of 1.67.
d.complements, and have a cross-price elasticity of 1.67.
4. The followig diagram shows two budhet lines:A and B
(圖略)
Which of the following explain the change in the budget line from A to B?
a.a decrease in income and a decrease in the proce of X
b.a decrease in income and an increase in the proce of X
c.an increase in income and a decrease in the proce of X
d.an increase in income and an increase in the proce of X
5. If MUx/Px < MUy/Py, then
a.spending a dollar less on Y and a dollar more on X increases utility.
b.spending a dollar less on X and a dollar more on Y increases utility.
c.X is more expensive than Y.
d.Y is more expensive than X.
6. Laura consumes only beer and chips. Her indifference curves are all bowed
inward. Consider the bundles (1,5), (3,3), and (5,1). If Laura is indifferent
between (1,5) and (5,1), then Laura must
a.prefer (5,1) to (3,3).
b.prefer (1,5) to (3,3)
c.prefer (3,3) to (1,5).
d.be indifferent between (3,3) and (5,1).
7. Suppose that for a particular firm the only variable input into the
production process is labor and that output equals zero when no workers are
hired. In addition, suppose that when four units of output are produced, the
total cost is $175, and the average variable cost is $33.75. What would the
average fixed cost be if ten units were produced?
a.$4
b.$10
c.$40
d.$135
8. When firms are said to be price takers, it implies that if a firm raises its
price,
a.buyers will go elsewhere.
b.buyers will pay the higher price in the short run.
c.competitors will also raise their prices.
d.firms in the industry will exercise market power.
9. In the short- run average costs eventually increase because of ________, and
in the long run average costs eventually increase because of ________.
a.diminishing returns; diseconomies of scale.
b.diseconomies of scale; diminishing returns.
c.constant returns to scale; decreasing returns to scale.
d.increasing returns to scale; diseconomies of scale .
10. In the long run, a firm will exit a competitive industry if
a.total revenue exceeds total cost.
b.the price exceeds average total cost.
c.average total cost exceeds the price.
d.Both a and b are correct.
二、問答題(50%)
1. 下圖分別是成人(adult)與兒童(child)市場對香煙的需求曲線，請回答以下問題；
(圖略)
1) 若香菸的價格為50元，以點彈性的觀念來看，那個市場較有彈性，為什麼?(3%)
2) 若香菸的價格由50元漲到60元，請用弧彈性的概念分別算出成人與兒童市場的
需求彈性值，用文字說明你算出的答案。(6%)
3) 承上題，香菸價格的上漲將導致成人與兒童對於香菸的花費分別是增加或減少？
為什麼？用你算出的彈性值 解釋。(6%)
2. 假設MRS=MUm/MUa，個人預算限制線的斜率Pa/Pm，消費者的所得為10元。請根據
下圖回答以下問題：
(圖略)
1) 請你寫下消費者追求效用極大下的最適選擇(maximizing rule)。(3%)
2) 假設M&Ms的價格為2元，則消費者追求效用極大下的消費選擇為圖上哪一點？請用
邊際效用分析法說明(3%)
3) 假設M&Ms的價格為1元，C點是否為消費者追求效用極大下的選擇？如果不是，C點
要如何改變才能達到效用極大？請用邊際效用分析法說明。(3%)
4) 請根據上圖畫出M&Ms個人需求曲線。(6%)
3.請你畫出短期經濟利潤為正的完全競爭廠商MC、ATC與AVC相對位置，並且回答以下問
題：
1) 寫出短期完全競爭廠商追求利潤極大化的最適選擇(maximizing rule)，且圖示之。
(3%)
2) 當短期時，經濟利潤為正的利潤、總成本(TC)、總變動成本(TVC)以及總固定成本
(TFC)為多少？(請用圖形面積表示)(8%)
3) 請問短期時完全競爭廠商的供給曲線是哪一段？解釋其經濟意義。(3%)
4) 請問短期時完全競爭廠商所面對的需求曲線是哪一條？解釋其經濟意義。(3%)
5) 該廠商的短期時有沒有可能面臨虧損還繼續生產？為什麼？(3%)
參考答案：
一、
CCCDA、CAAAC
二、
1.
(1)child，因為經過相同的E點，但child市場的需求線較平。(3%)
(2)Adult: 11/19；P增加1%會導致Adult的需求量減少11/19%。(3%)
Child: 11/9；P增加1%會導致Child的需求量減少11/9%。(3%)
(3)Adult的總支出增加(500 540)，因為P增加的百分比大於Q減少的百分。(3%)
Child的總支出增加(500 480)，因為P增加的百分比小於Q減少的百分比。(3%)
2.
(1)MUm/MUa=Pm/Pa
(2)A點 (3%)
(3)否，所以M增加A減少才能使得效用極大。(3%)
3.
(1) MR=AR=P=MC (3%)
(3) 短期完全競爭廠商的供給曲線為A點以上的P=MC線段。其中，A點為AVC的最低點且與
MC相交。P=MC表示廠商多提供一單位商品的最低價格為他生產此單位商品所衍生的
邊際成本。(3%)
(4) 由於個別廠商為price taker，市場價格由市場供給與市場需求所共同決定，廠商無
力影響。在這個固定價格下不論個別廠商生產多少有限的商品數量，都能被市場上
的消費者所需求，因此個別廠商所面對的需求曲線為AR=P。(3%)
(5) 停業點為價格低於AVC的最低處，即為A點。若價格介於ATC與AVC兩者最低處間，即A
、B兩點之間，廠商有可能在短期時面臨虧損卻繼續生產。此時雖然廠商只能賺得負
的經濟利潤，但是繼續營業不但可以支付營業所產生的總變動成本，還能賺回部份
的固定成本；然而停產則必須虧損全部的固定成本，所以在此情況中廠商雖然有虧
損但是必然會繼續營業。(3%)
--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 220.133.14.232
※ 編輯: hsin0331 來自: 220.133.14.232 (11/14 13:03)