A lubricant often has to perform many duties in any situation, in addition to its fundamental job of （）.

A.give the pressure
B.give the contents
C.give the shape of the tank
D.give the accuracy level

A.inefficient cooling
B.a leaking air start valve
C.a clogged drain valve
D.a leaking air bottle

A.a flame trap
B.a relief valve
C.a fusible plug
D.a bursting cap