— Dressed in a red coat, he is like a girl rather than a boy.

— ______ I didn’t recognize him.

No wonder           B. No way           C. No doubt         D. No problem

石门揭穿突出煤层在工作面距煤层法线距离（）之外，至少打2个前探钻孔，掌握煤层赋存条件、地质构造、瓦斯情况。

A．10m

B．15m

C．20m

D．25m