产后发热的治疗应以哪项为主（）
A.调气血，和营卫
B.清热解毒退热
C.活血化瘀清热
D.养血清热
E.疏风清热
参考答案：A
烟气流速增加一倍，对流受热面管子磨损速度增加（）倍。
A.5
B.6
C.7
D.8
A chain bridle is used when towing astern because it（）.
A.is easy to connect
B.provides an effective catenary and absorbs shock due to its weight
C.makes rigging a swivel unnecessary
D.prevents the tow from yawing by the drag of the chains in a seaway
