单项选择题
Air trapped in the hydraulic fluid of a steering system should be indicated by （）.
A.the pump over-speeding B.an improper rudder response C.bubbles in the sight glass D.ram relief valves lifting
单项选择题 Overgreasing of ball bearings installed on pumps will result in （）.
单项选择题 The energy associated with molecules is known as （）.
单项选择题 “Flooding back” is a condition where the liquid refrigerant （）.
