倒位可以抑制或降低基因的重组。( )
参考答案:对
—Look! The telephone is broken. Someone damaged it purpose.
—That may be right. But perhaps it was broken accident.
A.on; by
B.by; by
C.on; on
D.by; on
三相异步电动机的反接制动,方式简单、可靠,但振动冲击力大,一般适用于()4kW的电动机且启动不太频繁的场合。
A.大于
B.等于
C.小于
D.都可以