问题 不定项选择
不定项选择
关于密闭容器中气体的压强,下列说法中正确的是(   )
A.是由气体受到的重力所产生的    

B.是大量气体分子频繁地碰撞器壁所产生的    

C.压强的大小只取决于气体质量的大小    

D.容器运动的速度越大,气体的压强也就越大

答案

答案:B

单项选择题
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.

Macdonald had to seek support from the college captains because ______.

A.the public imagined he was not competent to command his crew

B.the Chief Coach Topolski lost the experienced American oarsmen

C.the Oxford crew was unlikely to win the Race without the Americans

D.the Americans would leave the squad unless they were to lead it