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问题 解答题
化简；
（1）
sin(π+α)sin(2π-α)cos(-π-α)
sin(3π+α)cos(π-α)cos(
3π
2
+α)

（2）cos20°+cos160°+sin1866°-sin（-606°）
答案

（1）原式=

-sinα(-sinα)(-cosα)
-sinα(-cosα)sinα
=-1；

（2）原式=cos20°-cos20°+sin（5×360°+66°）-sin（-2×360°+114°）

=sin66°-sin114°

=sin66°-sin（180°-66°）

=sin66°-sin66°

=0．

单项选择题

Many researchers have found greater dependence and obedience in very young girls, greater autonomy and activity in boys. When a barrier is set up to separate children from their mothers, boys try to knock it down; girls cry helplessly. There is little doubt that mother’s encouragement or discouragement—of such behavior plays a major role in determining adult personality. For example, a mother often stimulates male autonomy by throwing a toy far away from her young son, thus silently suggesting to him that he leaves her to get it.
Animal studies suggest that there may be a biological factor in material behavior; mothers of some monkeys punish their male babies earlier and more often than their female offspring; they also touch their female babies more often and act more protectively toward them.
As for the controversial question of female "passivity", psychologist Helen Deutsh believes that the concept has been misunderstood. "There is no contradiction between being feminine and working. The self can be active in both men and women," she says. It is only in love and sex that passivity is particularly appropriate for women. As she sees it, passivity is no more than a king of openness and warmth; it does not mean "inactivity of emptiness".
Another controversy ranges over the effect of hormones. Aggressive women; who discount hormonal influence, disagree violently with scientific researchers, who almost unanimously agree that hormones help determine how people feel and act. So far, there have been few studies of male hormones, but scientists think they may eventually discover hormonal cycles in men that produce cyclic changes in mood and behavior. As for females, studies have indicated that 49 percent of female medical and surgical admissions, most psychiatric hospital admission and 62 percent of violent crimes among women prisoners are related with hormonal cycles in women.

According to Helen, the word "passivity" underlined in Paragraph 3 means ______ .

A．passive to workmates

B．passive to lovers
C．selfness and indifference

D．dullness and keeping to oneself
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判断题

债券按发行价格可以分为：平价发行、折价发行和溢价发行。 ( )
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