硝普钠作用是（）
A.减弱心肌收缩力
B.降低心脏前负荷
C.降低心脏后负荷
D.降低心脏前后负荷
E.降低心脏后负荷及增加心肌刺激
参考答案：D
请根据答句写问句。
1. _____________________________? I'll go there on foot.
2. _____________________________? He'll go to the park.
3. _____________________________? She's going to read books.
4. _____________________________? We'll have an English class.
5. _____________________________? They're going to play soccer.
变形缝按( )计算建筑面积。
A．自然层 B．标准层C．水平投影 D．结构外围
