单项选择题
Some refrigeration systems have chemical moisture indic...
单项选择题Some refrigeration systems have chemical moisture indicators installed in conjunction with the sight glass in the liquid lineIf excess moisture is present in the system, the indicator will （）
A.activate the driers B.change color C.secure the compressor D.add a predetermined amount of liquid drier
In the navigation, cause the shafting over load most ea...
单项选择题In the navigation, cause the shafting over load most easily（）
A.stopping the main engine suddenly B.changing the main engine running direction suddenly C.the sailing from the shallow water area to the deep water area D.the ship’s trim too much
The oil index of main engine should be controlled to pr...
单项选择题The oil index of main engine should be controlled to prevent it from in heavy weather（）
A.over heat B.over speed C.over pressure D.over worn
