A.5~10 B.10~15 C.15~20
A.低速擋 B.中速擋 C.高速擋
A.質(zhì)量大,熱膨脹系數(shù)小 B.質(zhì)量小,熱膨脹系數(shù)大 C.慣性力小,熱膨脹系數(shù)小 D.質(zhì)量小,慣性力大