哌替啶用于：
A. 各种锐痛
B. 人工冬眠
C. 心源性哮喘
D. 麻醉前给药
吗啡用于：
A. 分娩镇痛
B. 各种锐痛
C. 心源性哮喘
D. 急慢性消耗性腹泻
The opportunity cost of making a component part in a factory with excess capacity for which there is no alternative use is:
A. the variable manufacturing cost of the component.
B. the total manufacturing cost of the component.
C. the fixed manufacturing cost of the component.
D. zero.
Which of the following costs are always irrelevant in decision making?
A. avoidable costs
B. sunk costs
C. opportunity costs
D. fixed costs
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