电动车窗主要由哪些部件组成？其中升降机构有哪几种？

You board an inflatable liferaft that has been hand launched from a sinking vessel. What should you do first after everyone is onboard the liferaft?（）.

A.Cut the painter

B.Operate the radio equipment

C.Open the equipment pack

D.Ventilate the liferaft of CO₂