Wind power is an ancient source of energy _________ we may return in the near future.

A． on which

B． by which

C． to which

D． from which

[单选题]Heat energy is a source of power, but （） will cause damage to the engine.A . excessive heatB . insufficient heatC . effective coolingD . high output

[判断题] 英文POWER和POWER SOURCE的意思都是电源。（）A . 正确B . 错误

[单选题]The power transformer is used to change( )of the power grid for the purpose

The girl was a-|||-member of an ancient population that the report authors have

The girl was a-|||-member of an ancient population that the report authors have

[名词解释] 碳源（source ofcarbon）

[名词解释] 氮源（source ofnitrogen）

[试题]TheancientEgyptiansaresupposed_________rocketstothemoon.A．)tosendB)tobesendingC．)tohavesentD)tohavebeensending

[单选题]An instrument that indicates wind direction is known as a(n)（）.A . weather vane，wind vane or wind sockB . hydrometerC . hygrometerD . sling psychrometer

[单选题]An example of a primary source of liquidity is:A.Liquidating assets.B.Negot