有地热问题的矿井，地下水温高，当采掘工作面接近积水区时，煤壁的温度和空气的温度也升高。
参考答案：对
One of the customs officers, who was watching the arrivals very ______, saw feathers ______ from under
a woman's coat.[ ]
A. closely; falling
B. close; fall
C. closely; fall
D. close; falling
切断机在运转正常后方可断料，断料时手与切刀之间的距离不得小于（），活动刀片前进时不应送料。
A.100mm
B.150mm
C.200mm
D.250mm
