患者，男，65岁。久咳不止，咳声低微，少气乏力，痰少而干，痰中夹有血丝。宜首选的药物是（）
A.人参
B.西洋参
C.黄芪
D.甘草
E.山药
参考答案：B
Where did Columbus first set foot on the New Continent
A．Watling Island.
B．At the spot where a carved stone was erected to mark the event.
C．Somewhere in eastern Bahamas.
D．No consensus has been reached on the event among historians.
预制钢筋混凝土板的支承长度，在墙上不宜小于（）
A、80mm
B、100mm
C、150mm
D、200mm
