(A)三角形 (B)梯形 (C)鋸齒形
(A)整體式滑動(dòng)軸承 (B)整體式軸瓦軸承 (C)對(duì)開式軸瓦軸承 (D)滾動(dòng)軸承
(A)50% (B)60% (C)70% (D)80%