额中回后部是()
A.运动性语言中枢
B.听觉性语言中枢
C.书写中枢
D.视觉性语言中枢
E.内脏运动中枢
参考答案:C
The train _____ at the present speed until it reaches the foot of the mountain at about nine o’clock tonight.
A.went
B.is going
C.goes
D.will be going
有一物体放在凸透镜前,到凸透镜的距离是20厘米,此时在屏上得到的是放大的像,则此凸透镜的焦距可能是( )
A.4厘米
B.8厘米
C.16厘米
D.22厘米