蜗杆传动工作时,效率一般为0.7~0.8,具有自锁时效率小于()。
A. 0.5
B. 0.6
C. 0.7
D. 0.8
A．traditional.B．more melodic.C．very repetitive.D．commonly played.
A. traditional.
B. more melodic.
C. very repetitive.
D. commonly played.
A．The girl refused to refund the jeans.B．He was given the wrong size.C．The girl delibe
A. The girl refused to refund the jeans.
B. He was given the wrong size.
C. The girl deliberately put the jeans in box.
D. The girl didn't handle his complaint well.
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