兴奋通过1个突触所需的时间为()
A.0.1~0.3ms
B.0.3~0.5ms
C.0.5~0.7ms
D.0.7~0.9ms
E.>0.9ms
参考答案:B
25.Can you explain ____ most deserts are located near the west coast of the continents?
A.why is it that
B.why it is that
C.how it is that
D.how is it that
()是一种单置式推力轴承,其结构复杂,瓦块可倾斜,受力均匀,承载能力大,常用于高速、重载部位。
A、空心推力轴承
B、环形肩推力轴承
C、环形垫推力轴承
D、米歇尔推力轴承