初次运用或长期停放的柴油机启动前需要排放()的存油。
A.油底壳油池
B.机油滤清器
C.燃油污油箱
D.增压器
参考答案:A, B, D
There was an oil painting _______ in the corner. It _______ there for several days.
A.laying; had laid
B.lain; had laid
C.lying; had lain
D.laid; had been lain
一物体自t=0时开始做直线运动,其速度图线如图所示。下列选项正确的是
A.在0~6s内,物体离出发点最远为35m
B.在0~6s内,物体经过的路程为40m
C.在0~6s内,物体的平均速度为7.5m/s
D.在5~6s内,物体做减速运动