34.The timing for each starting valve must be set so that it opens when the piston is .
(A)just past the top-dead-center（TDC）
(B)just past the bottom-dead-center（BDC）
(C)on the way upward
(D)just before the bottom-dead-center（BDC）

答案：登入後查看
統計： A(39), B(12), C(5), D(6), E(0) #1188702