人类免疫缺陷病毒存在于受感染者的________、_____、______、_________中。
参考答案：血液；精液；唾液；泪液中
甲氨蝶呤的不良反应是（）
A.心脏损害
B.高尿酸血症
C.末梢神经炎
D.口腔溃疡
E.出血性膀胱炎
Assume that for the average consumer, the quantity demanded for jeans increases from 5 to 7 pairs per year in response to a price decrease from $ 29 to $ 24 per pair. The price elasticity and relative elasticity of demand for jeans is best described by which of the followingPrice elasticity of demand Relative elasticity （） ①A. -1.77 Relatively inelastic ②B. -2.32 Relatively elastic ③C. -1.77 Relatively elastic
A. ①
B. ②
C. ③
