辊轴（摇轴）支座使用时，其构造的最大纵向位移应满足以下要求：摇轴倾斜角不应大于（）。
A.5°
B.6°
C.7°
D.8°
参考答案：C
—It’s a pity that I can only live here for two days _______.
—Why not stay for another day? I know you have three days off.
A．at first
B．at last
C．at least
D．at most
导爆管抗电性能为（）KV静电，爆速1600-2000m/s。
