一般将限位开关的位置调整在轿厢超越端站平层位置（）mm时动作。
A.10～20
B.20～40
C.30～40
D.30～50
参考答案：D
Mr. Taylor, of the urban life, is considering his last years in the countryside after his retirement.
A．tiring; spend
B．tired; to spend
C．tiring; spending
D．tired; spending
发病率最高的髓内肿瘤是（）
A.少突胶质细胞瘤
B.脊膜瘤
C.血管性肿瘤
D.星形胶质细胞瘤
E.室管膜瘤
