VitB12测定对下列哪种疾病诊断有价值（）
A.再生障碍性贫血
B.巨幼细胞性贫血
C.缺铁性贫血
D.白血病
E.PNH
参考答案：B
已知集合M={x|x2＜4}，N={x|x2-2x-3＜0}，则集合M∩N=[ ]
A、{x|x＜-2}
B、{x|x＞3}
C、{x|-1＜x＜2}
D、{x|2＜x＜3}
If the center of low pressure is due west of you in the Northern Hemisphere，which wind direction should you expect（）.
A.South to west
B.South to east
C.West to north
D.North to east
