A.60~80 B.70~90 C.120~145
A.零部件轉(zhuǎn)動靈活 B.限位器動作正確 C.犁刀口無鈍口 D.下托輥座應牢固、不轉(zhuǎn)動
A.5 B.10 C.15 D.20