There are two general types of fuel systems, which are _______ systems.
A.fuel pump and boost pump
B.fuel pump and gravity-feed
C.boost pump and gravity-feed
D.either A or C
正确答案是B
There are two general types of fuel systems, which are _______ systems.
A.fuel pump and boost pump
B.fuel pump and gravity-feed
C.boost pump and gravity-feed
D.either A or C
正确答案是B