A.5m B.10m C.15m D.20m
A.設(shè)在低處敷設(shè) B.設(shè)在中間處敷設(shè) C.應(yīng)在高處敷設(shè) D.無要求
A.0.01~0.1兆帕 B.0.1~0.15兆帕 C.0.2~0.7兆帕 D.1~2兆帕