A.8 B.10 C.12 D.14
A.70% B.80% C.90% D.100%
A.10% B.20% C.25% D.30%
A.100%二氧化碳 B.100%氩气 C.100%氦气 D.2%氧气+98%氩气 E.80%氩气+20%二氧化碳
A.减速器 B.卷筒 C.驱动齿轮 D.制动器