假定一块土地上仅种高粱和大豆两种,那用这块地种高粱的机会成本就是种大豆可能带来的收益。
参考答案:错
选择恰当的选项补全话,其中两项是多余的。
A : Hi, Bob. What does your mother do?
B : 1
A : Where does she work?
B : 2
A : Do you want to be a doctor, too?
B :Oh, no, no. 3
A : Why? I think it's a hard job.
B: 4 , but 5
A : Maybe.
A. She works in a hospital.
B. She is a nurse.
C. I want to be an actor.
D. it's exciting
E. It's dangerous.
F. She. is a doctor.
G. It's difficult
不属中暑先兆的临床表现是()
A.大量出汗
B.头晕头痛
C.脉搏细速
D.口渴胸闷
E.四肢无力