额定速度V≤2.5m/s的交、直流调速电梯,轿厢在空载和额定载荷范围内的平层精度,应在();mm范围内
A.±10
B.±15
C.±20
D.±30
参考答案:B
— Would you mind my _____ here?
— Sorry, you'd better not. [ ]
A. smoke
B. to smoke
C. smoking
慢性白血病特点是()。
A.骨髓内原始细胞<5%
B.骨髓内原始细胞>20%
C.骨髓内原始细胞>40%
D.骨髓内原始细胞>30%
E.骨髓内原始细胞<2%