单项选择题
The ()has a water damp ring.
A.purifier B.oil/water separator C.incinerator D.distiller
单项选择题 Duty officer informs us that the vessel is out of harbor and in “Full Ahead”We are going to run ().
单项选择题 The bearing cap and shell are replaced and tightened up until ().
单项选择题 In ()the control action is independent on the output.