A.0.5% B.1.0% C.1.5% D.0.1%
A.1%-3% B.3%-4% C.4%-5% D.5%-6%
A.區(qū)域切冒和壓垮冒頂 B.推垮和壓垮型冒頂 C.局部冒頂和大冒頂 D.局部壓垮和大冒頂