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北京时间2009年3月1日16时13分10秒，“嫦娥一号”卫星在北京航天飞行控制中心科技人员的精确控制下，准确落于月球东经52.36度、南纬1.50度的预定撞击点，“受控撞月”成功．“嫦娥一号”卫星首次使用了重庆西南铝铝材生产开发公司研制的铝合金专用材料---铝锂合金板材．关于合金，下列说法正确 的是（　　）

A．合金是化合物

B．合金的硬度一般比各成分金属大

C．多数合金的熔点高于组成它的成分金属

D．合金只能由金属与金属熔合而成

答案

A、根据合金的概念，合金属于金属材料是混合物，故错；

B、合金的硬度比组成合金的各成分硬度高，故正确；

C、合金的熔点比各成分的熔点低，故错；

D、合金是金属与金属或金属于非金属的混合物，故错．

故选B．

问答题

primer; probe
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单项选择题

Oxford and Cambridge University Boat Clubs have both taken the opportunity to travel to Spain this month to train in less testing weather conditions than those which have, quite literally, already blown around the UK in January of 2007.
Each group of athletes has been focused on training to the maximum, working on technique and molding themselves into two potential fighting units per Club for the 2007 Boat Race, sponsored by Xchanging. One set will be in the Blue Boat for each club and one set will race as reserves in Isis, for Oxford, and Goldie, for Cambridge.
In these modern times, the Head Coach for each club has a huge input on selection even though the crew is still named by the President. Just twenty years ago the balance was not quite the same.
The year 1987 will always be remembered in the history of this great Race as the year of the "mutiny" at Oxford. It is a tale which has since been retold and reworked in both a book and a movie.
This was the season for which mature Scottish student, Donald Macdonald, was elected President, having all ready won a Blue in 1986. Macdonald re-appointed Daniel Topolski (now a renowned rowing journalist and broadcaster)as Chief Coach.
Part of the 1986/87 squad at Oxford included American Chris Clark, now a coach at an American University, and four fellow US internationals.
Allegedly, a split appeared in the squad between the American quintet, all experienced and leading oarsmen, and those rowers closest to Macdonald. The Scot’s group were happy to follow Topolski’s regime whilst the others were not so sure.
Following a contentious seat racing trial in January of 1987, Topolski decided to move Clark to the bow-side of the beat. Clark disagreed. Topolski held firm. As a result Clark and his" group" within the squad decided not to row and sought a takeover.
The squabble was played out extensively in the UK national media and caught the public imagination. Macdonald sought support from the college captains and eventually won a vote of confidence by 28 votes to 11.
Without the Americans, the Oxford crew was immediately considered a lost cause. Cambridge were overwhelming favorites to win.
As it turned out, though, this was a Race which would prove why sport, and particularly The Boat Race, can be so fascinating.

The phase" blown around" underlined in Paragraph 1 is closest in meaning to ______.

A．discuss

B．walk around

C．doubt

D．visit
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