与乳腺癌发病无关的是
A．雌酮和雌二醇B．月经初潮年龄早C．绝经年龄晚D．一级亲属中有乳腺癌病史者E．吸烟
参考答案：E
低瓦斯矿井中哪些区按高瓦斯矿井管理？
Serving is（）.
A.marine or ratline would along the grooves of a rope
B.narrow strips of light canvas or cotton cloth spiral-wrapped along the rope
C.marline tightly wound on the rope by means of a board or mall
D.a splice made by laying the strand of one rope into the vacated grooves of another rope
