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发布时间：2022-01-07
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在等差数列{an}中，已知a5+a8=5，那么a2+a11的值为（）A.5B.10C.15D.2
在等差数列{an}中，已知a5+a8=5，那么a2+a11的值为（）
A.5
B.10
C.15
D.20
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A. 5%
B. 10％
C. 15%
D. 20%
E. 25%
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更多“在等差数列{an}中，已知a5+a8=5，那么a2+a11的值为（）A.5B.10C.15D.2”相关的问题
第2题
已知向量a =(3,4),b= (0, - 2),则 cos〈a,b〉=()。A.4/5B.-4/5C.2/25D.-2/25
已知向量a =(3，4)，b= (0， - 2)，则 cos〈a，b〉=（）。
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A.4/5
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第3题
在?ABC中 ,已知a=1,b=2, cosC=-1/4(1)求 ?ABC 的周长;(2)求 sin(A+ C ) 的值.
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（1）求 ?ABC 的周长；
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第5题
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某同学每次投篮投中的概率为2/3该同学投篮2次，只投中1次的概率为()。
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A.6/25
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第7题
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A.甲既不是乙的充分条件，也不是乙的必要条件
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第9题
Generations of Americans have been brought up to believe that a good breakfast is one life’s essentials. Eating
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breakfast at the start of the day, we have all been told, and told again, is as necessary as putting gasoline in the
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efforts, they still take no breakfast. Between 1977 and 1983, the latest year for which figures are available, the
number of people who didn’t have breakfast, increased by 33 percent.
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in the last few years indicate that, for adults especially, there may be nothing wrong with omitting breakfast.
“Going without breakfast does not affect performance,” said Arrold E. Bender, former professor of the nutrition
at Queen Elizabeth College in London, “nor does giving people breakfast improve performance.”
Scientific evidence linking breakfast to better health or better performance is surprisingly inadequate, and most
of the recent work involves children, not adults, “The literature”, says one researcher, Dr. Erresto at the University
of Texas, “is poor”.
The latest year for which figures could be obtained is _______.
A. the year the author wrote the article
B. 1977
C. any year between 1997 and 1983
D. 1983
