单项选择题
A.faster than dead slow speed
B.slower than dead slow speed
C.with the output of MCR
D.at critical speeds
单项选择题 To counteract these undesirable effects cylinder oils usually contain additives formulated to impart a high degree of （） and detergency.
单项选择题 To avoid scavenge fires occurring the engine timing and equipment maintenance （）.
单项选择题 To avoid scavenge fires （） the engine timing and equipment maintenance should be correctly carried out.