单项选择题 Which of the diesel engine components listed increase air density and helps to improve engine operating efficiency?（）

单项选择题 By comparing the exhaust gas temperature of each cylinder, the operator can determine if the load is balanced throughout the engine. The device most commonly used is a（）

单项选择题 To shut down a diesel engine after it exceeds the set maximum speed，which type of device listed should be used?（）