单项选择题
A.往复泵 B.喷射泵 C.离心泵 D.回转泵
A.沿墙 B.沿地板 C.沿天棚 D.沿(跨)屋架(梁)下弦
A.80~100mm B.80~150mm C.100~150mm D.120~150mm