单项选择题

An instrument that maintains a continuous record of humidity changes is called a（）.

A.thermometer
B.barometer
C.hygrograph
D.thermograph

点击查看答案&解析

上一题目录下一题

相关考题

单项选择题

An instrument that indicates wind direction is known as a(n)（）.

A.weather vane，wind vane or wind sock
B.hydrometer
C.hygrometer
D.sling psychrometer

单项选择题

All of the following steps are taken in starting a centrifugal pump，EXCEPT to（）.

A.set the relief valve
B.check the lubrication system
C.vent the pump casing
D.open the pump suction and discharge valves

单项选择题

After an engine is started you should（）.

A.increase engine speed to insure adequate flow of oil to all parts of the engine
B.pay no attention unless there are unusual noises from the engine
C.check operating pressures and temperatures，and check for leaks
D.run the engine at idle until the temperature has increased