99色精品-9色在线-99色在线-99色视频 国产欧美日产一区二区三区_亚洲精品亚洲人成在线观看_四虎在线精品永久观看_免费一级a一片久久精

單項(xiàng)選擇題

Which of the following conditions is most likely to occur when unburned fuel contaminates the crankcase of a diesel engine?()

A.Lube oil is diluted and its viscosity is reduced
B.Sulfuric acid is formed
C.Bearings become pitted ad immediately fail
D.Valve stems develop sludge deposits

微信掃碼免費(fèi)搜題