为保证柴油机寿命和安全可靠的运行，并控制（），柴油机不允许在超过冒烟界限的情况下工作。
A.排气污染
B.扬尘污染
C.噪声污染
参考答案：A
如何从法律角度完善我国纳税 * * 利保障？
A car traveled 462 miles per tankful of gasoline on the highway and 336 miles per tankful of gasoline in the city. If the car traveled 6 fewer miles per gallon in the city than on the highway, how many miles per gallon did the car travel in the city ？（）
A．14
B．16
C．21
D．22
E．27
