建筑边坡采用预应力锚杆进行支护时,其自由段长度为()。
A.不小于4m
B.不小于5m
C.不小于5m且应超过潜在滑裂面
D.不小于5m且不应超过潜在滑裂面
参考答案:C
可获得最大传动比的传动方式是().
A.带传动
B.齿轮传动
C.涡轮、蜗杆传动
Whenever we were ___, he is always ready to ___ us some help.
A.in the trouble; give
B.in trouble; offer
C.in a trouble; pay
D.in trouble,take