小官极速搜题练习工具
某矿体不支护暴露面积在50~200㎡以内,其稳定性为____。A.不稳固矿体B.中等稳固矿体C.稳固矿体D.极稳固矿体
【正确答案】B
Copyright © 2026 极搜搜 | Powered by Specia WordPress Theme 沪ICP备2021005711号-2