50. 哪一個含氮鹼基存在於RNA而不存在於DNA?
(A) 尿嘧啶(uracil)
(B) 胞嘧啶(cytosine)
(C) 鳥嘌呤(guanine)
(D) 胸腺嘧啶(thymine)

46. 下列哪一個選項是一莫耳 HCl 與一莫耳 1-丁炔反應的產物? (A) 1-氯-1-丁烯 (B) 1-氯-2-丁烯 (C) 2-氯-1-丁烯 (D) 氯乙烷 + 乙炔

47. 下面化合物的IUPAC系統命名是 (A) 4,5-diethylheptane (B) 3-propyl-4-ethylhexane (C) 2-ethyl-3-propylhexane (D) 3-methyl-4-propylheptane

48. 葡萄糖分子(結構如下)有幾個掌性中心? (A) 1 (B) 2 (C) 3 (D) 4

49. 以下哪種聚合物是經由縮合反應形成的? (A) 鐵氟龍(Teflon) (B) 尼龍(nylon) (C) 壓克力(Plexiglas) (D) 合成橡膠(neoprene)

1. Which of the following is a function of money? (A) a unit of account (B) a store of value (C) medium of exchange (D) All of the above are correct.

2. A deadweight loss is a consequence of a tax on a good because the tax (A) induces the government to increase its expenditures. (B) induces buyers to consume less, and sellers to produce less. (C) increases the equilibrium price in the market. (D) imposes a loss on buyers that is greater than the loss to sellers.

3. For a monopolist, marginal revenue is (A) equal to price, as it is for a perfectly competitive firm. (B) less than price, as it is for a perfectly competitive firm. (C) equal to price, whereas marginal revenue is less than price for a perfectly competitive firm. (D) less than price, whereas marginal revenue is equal to price for a perfectly competitive firm.

4. If the cross-price elasticity of two goods is negative, then the two goods are (A) normal goods. (B) inferior goods. (C) substitutes. (D) complements.

5. Mrs. Smith operates a business in a competitive market. The current market price is $8.10. At her profit-maximizing level of production, the average variable cost is $8.00, and the average total cost is $8.25. Mrs. Smith should (A) continue to operate in the short run but shut down in the long run. (B) shut down her business in the short run but continue to operate in the long run. (C) continue to operate in both the short run and long run. (D) shut down in both the short run and long run.

6. Suppose good X has a negative income elasticity of demand. This implies that good X is (A) a normal good. (B) an inferior good. (C) a necessity. (D) luxury.