发动机冷车启动时，空气与燃料混合比约多少？（）
A.5～7
B.8～10
C.12～14
D.16～18：1
参考答案：B
— Bob! Is this your dictionary?
— No, it isn't. Ask Sally. She is looking for ______. [ ]
A. his
B. hers
C. mine
D. yours
拉运火工品的车辆配备什么防护设施？
