97免费在线观看视频,亚洲综合自拍网,黄色毛片免费观看,热久久综合网,免费看日产一区二区三区 狠狠操av,久久久涩涩涩,在线精品免费视频,人人插天天干,久久91精品国产91久久

單項(xiàng)選擇題

Oil oxidation, as a result of excessively high lube oil temperature, is harmful to a diesel engine because ()

A.oil foaming will occur
B.large quantities of oil are consumed
C.lube oil viscosity is always decreased
D.corrosive by-products are usually formed

微信掃碼免費(fèi)搜題