A.游絲彈簧失效 B.傳動(dòng)件生銹 C.夾有雜物 D.沒(méi)有通氣
A.1/3-2/3 B.1/4-1/3 C.1/4-1/2 D.1/3-3/4
A.10% B.15% C.20% D.30%