A.來回串動幾次,返水正常后繼續(xù)鉆進(jìn) B.給進(jìn)快速通過 C.停止鉆進(jìn)留下班處理 D.根據(jù)現(xiàn)場而定
A.50 B.30 C.20 D.40
A.5% B.3% C.7% D.10%