In the fresh water system the heating medium usually is _.

This is a highly ___ new heating system.A. efficiencyB. efficientC. efficiently

[单选题]Fresh water is used for the cooling of cylinder jackets and （） of the marine diesel engine.A . cylinder coversB . lubricating spaceC . crossheadD . exhaust manifold

[单选题]（） water is more expensive than fresh water It has high specific heat and low viscosity.A . DistilledB . DistillingC . BoilingD . Boiled

[单选题]In the closed cooling system, the water （）.A . is made to circulate out of the systemB . is made to circulate within the systemC . is made circulate within the systemD . is made circulate out of the system

[单选题]There is （） in any water cooling system for a diesel engine allowing for expansion and water make-up in the system as well as air vent and chemicals addition.A . a setting tankB . a service tankC . a head tankD . an expansion joint

[单选题]In a diesel engine cooling water system, a pH of 60 indicates a/an （）.A . slightly acidic conditionB . slightly alkaline conditionC . overtreatment of waterD . neutral condition of water

[单选题][Fresh] studentsare usually very happy on the first day to go to college.A.

[单选题]The starting air system usually has （） to prevent starting if anything is not in order.A . stop valvesB . interlocksC . non-return valvesD . air vent

[单选题]A diesel engine cooling water system with a pH factor of 30 indicates a condition of （）.A . slight acidityB . slight alkalinityC . excessive alkalinityD . excessive acidity

[单选题]第一组A．n automatic system usually consists of a control system and an information system. A control system is a system which measures the condition of some entity and, with the information, governs the state of a variable; i.e., speed, temperature, pre