衡量消费者收入水平的指标主要包括( )。

A．人均国民收入

B．个人收入

C．个人可支配收入

D．税收收入

E．国民收入

When should distress flares and rockets be used? （）

A.Immediately upon abandoning the vessel

B.Only when there is a chance of their being seen by a rescue vessel

C.At one hour intervals

D.At half hour intervals