单项选择题
Why the cooling water of the diesel engine should be treated? Because the（）
A.Cooling water is alkalescence B.cooling water is acidity C.cooling water has salinity D.cooling water has impurity
单项选择题 The cooling water of the diesel engine should be treated, because it has（）
单项选择题 When received the order "finished with engine" which of the following operations is wrong?（）
单项选择题 When the diesel is stopped, which of the following items is wrong?（）
