凸轮式限速器适用于额定速度()的电梯。
A、0.5-1M/S
B、1-2M/S
C、0.5M/S以下
D、2M/S以上
参考答案:A
慢性肾衰竭必有的临床表现是()
A.高血钾
B.严重贫血
C.出血
D.乏力、头痛甚至抽搐
E.骨酸痛
She had _______ got out of the house _______ it began to rain.
A.no sooner… then
B.no sooner… than
C.hardly…than
D.hardly… then