现在武当山古建筑群主要包括（）、（）、（）、（）四座宫殿，玉虚宫、五龙宫两座宫殿遗址

按照与散客约定的送站时间，导游人员应提前（）到游客下榻的饭店。

A．1小时 

B．40分钟 

C．半小时 

D．20分钟

分解因式：a³﹣ab²=　   　．

Colleges in the US have added a new subject, “great chemistry”, to their curriculum today. “Green chemistry (53) how we can develop products that won’t (54) the environment,” explains Paul Anastas, director of Yale University’s Center for Green Chemistry and Green Engineering, opened at the beginning of this year. The American Chemical Society, (55) approves more than 600 college chemistry programs, only lists about a dozen that teach green chemistry. But that (56) is growing.
Cambridge College in Massachusetts is offering “ an introduction to green chemistry” course this gall and is offering the nation’s first bachelor’s and master’s (57) in green chemistry. The program will have classes in environmental science and even environmental (58) and policy. These subjects are not (59) taught to chemistry major.
Employers (60) the introduction of green chemistry. Businesses are increasing seeking graduates (61) backgrounds in the subject because it can help them make or save money in he development and manufacturing of products. “We need people who can not only understand their place (62) , but also understand the worldwide perspective,” said Adam Peterson, a chemical division manager at Dow Corning Corp.

A．which
B．that
C．such
D．thus

男，42岁，劳累后右髋骨轻微酸痛1年余，加重半个月，X线片发现右股骨颈及粗隆间膨胀性改变，中央透亮，边缘有硬化带，无骨折，考虑为骨囊肿，采取以下哪项措施（）。

A.截肢+化学治疗

B.化疗治疗+免疫治疗

C.中药治疗

D.病灶刮除并植骨

E.病段切除+人工假体移植

关于互斥型方案经济比选的说法，正确的是（　　）。

A．效益与费用都不同的方案比选可以采用费用现值法

B．互斥型方案比选不要求效益和费用的计算口径一致

C．互斥型方案比选需要考察各个方案自身的经济效果

D．采用价值性指标，必须分析方案闻的差额净现金流量