A.剛度太強(qiáng) B.剛度太弱 C.預(yù)壓縮量太大 D.聯(lián)接過緊
A.急流航段33s,其它航段60s B.急流航段12s,其它航段20s C.急流航段9s,其它航段15s D.急流航段25s,其它航段30s
A.25° B.35° C.40° D.45°