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问题 解答题

在△ABC中，a、b、c分别是角A、B、C所对的边，满足a2+c2-b2=ac．

（1）求角B的大小；

（2）若x∈[0，π），求函数f（x）=sin（x-B）+sinx的值域．

答案

（1）在△ABC中，由余弦定理得cosB=

a2+c2-b2
2ac
=
1
2

又∵B∈(0，π)，∴B=

π
3
；

（2）f(x)=sin(x-

π
3
)+sinx=
3
2
sinx-
3
2
cosx=
3
sin(x-
π
6
)

∵0≤x＜π，则-

π
6
≤x-
π
6
＜
5π
6

∴sin(x-

π
6
)∈[-
1
2
，1]

单项选择题

RDW与MCV同时增加最常见于（）

A.肾性贫血

B.PNH

C.甲状腺功能低下

D.再生障碍性贫血

E.巨幼细胞贫血
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问答题

Although Henry Ford’s name is closely associated with the concept of mass production,he should receive equal credit for introducing labor practices as early as 1913 that would be considered advanced even by today’s standards. Safety measures were improved, and the workday was reduced to eight hours, compared with the ten-or-twelve-hour day common at the time. In order to accommodate the shorter work day, the entire factory was converted from two to three shifts.
In addition, sick leaves as well as improved medical care for those injured on the job were instituted. (47)The Ford Motor Company was one of the first factories to develop a technical school to train specialized skilled laborers and an English language school for immigrants. Some efforts were even made to hire the handicapped and provide jobs for former convicts.
(48)The most widely acclaimed innovation was the five-dollar-a-day minimum wage that was offered in order to recruit and retain the best mechanics and to discourage the growth of labor unions. Ford explained the new wage policy in terms of efficiency and profit sharing. He also mentioned the fact that his employees would be able to purchase the automobiles that they produced—in effect creating a market for the product. (49)In order to qualify for the minimum wage, an employee had to establish a decent home and demonstrate good personal habits,including sobriety,thriftiness,industriousness,and dependability. (50)Although some criticism was directed at Ford for involving himself too much in the personal lives of his employees,there can be no doubt that,at a time when immigrants were being taken advantage of in frightful ways,henry Ford was helping many people to establish themselves in America.

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