Besides streamlining the nose of the airplane, the _______ helps cool the engine by ducting air around the cylinders.
A.propeller
B.cowling
C.firewall
D.hood
正确答案是B
Besides streamlining the nose of the airplane, the _______ helps cool the engine by ducting air around the cylinders.
A.propeller
B.cowling
C.firewall
D.hood
正确答案是B