The unit of electrical power is the _____.

When the water produced from most evaporator is supplied for drinking purpose, it must be treated to ensure it is biologically pure and _____.

When the fuel oil is burning in the combustion chamber, it _____.

大型低速柴油机的最低启动转速范围，一般为（）。

The most common type of containment device for spilled oil on the water is the use of _____.

If the engine does start on air, but combustion does not immediately begin, the cause may be _____.