BJ7型手抬机动消防泵采用单缸四行程()式发动机作动力。
(A)风冷
(B)水冷
(C)自燃
(D)自由
参考答案:A
下面哪一种类型不属于反向功控的()。
A、反向开环
B、反向闭环
C、反向内环
D、反向外环
Traffic restrictions have come into effect in Beijing _____ to improve the capital’s air quality
and traffic situation for the 2008 Olympics. [ ]
A. in order that
B. in an attempt
C. at an attempt
D. in a try