用平行光线照射物体,物体在投影面上所得的投影叫做()。
A.正面投影
B.侧面投影
C.平行投影
D.立体投影
参考答案:C
–I lost the watch that my uncle gave me as the birthday gift.
–Oh, _________.
A.that’s right
B.really
C.no worry
D.sorry to hear that.
麝香对心脏的效应为
A.抑制心肌收缩力
B.缓解心绞痛
C.抗心律失常
D.提高室颤阈
E.减慢心率