During the valve overlap period, the exhaust pressure of a turbochargers, four-stroke/cycle diesel engine must be less than the intake manifold pressure to ensure ()
A. effective cylinder scavenging and cooling
B. constant pressure from the turbochargers
C. cooler operation of the exhaust system
D. effective constant pressure for turbocharger operatio
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A. 正确
B. 错误
下列哪些系、离操作的做法正确?()I、抛起锚时人员不可站在锚链前方;II、靠泊时大副应随时报告船首前方距离;III、离泊时,二副应及时报告收缆情况;IV、只有经驾驶台同意,首尾方可系、解缆
A. I~III
B. II~IV
C. I~IV
D. IIV