3.发动机活塞环中的气环起的作用是

A.密封、散热                                                         B.散热、刮油

C.密封、润滑                                                         D.散热、泵油

4.属于稳定工况的是

A.怠速                                                                      B.冷启动

C.加速                                                                      D.暖机

5.冷却系统中起到控制流经散热器的水量作用的部件是

A.水泵                                                                      B.节温器

C.风扇离合器                                                         D.补偿水桶

6.赛车采用的发动机和传动系的布置方案是

A.前置发动机后轮驱动                                        B.前置发动机前轮驱动

C.中置发动机后轮驱动                                         D.前置发动机全轮驱动

7.在汽车横向平面内，主销上部向内倾斜一个角度，称为

A.车轮外倾角                                                         B.前轮前束

C.主销后倾角                                                         D.主销内倾角

8.铅蓄电池一般由3个或6个单格电池组成，每个单格电池之间则由______串联起来。

A.栅架                                                                      B.隔板

C.联条                                                                      D.极板

9.发动机点火时，油压指示灯亮，运转时随即熄灭，表示机油压力

A.过高