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问题 解答题

某体育用品厂，原来生产一种健康器的成本是450元，零售价是580元．现在经过改造以后生产成本下降20%，而利润要比原来再增加10%，那么现在零售价应定为多少元？

答案

（580-450）×（1+10%），

=130×1.1，

=143（元）；

450×（1-20%）+143，

=450×0.8+143，

=360+143，

=503（元）；

答：现在零售价应定为503元．

单项选择题

Research on animal intelligence always makes me wonder just how smart humans are. (91) the fruitfly experiments described in Carl Zimmer’s piece in the Science Times on Tuesday. Fruit flies who were taught to be smarter than the average fruit fly (92) to live shorter lives. This suggests that (93) bulbs burn longer, that there is an (94) in not being too terrifically bright.
Intelligence, it (95) , is a high-priced option. It takes more upkeep, burns more fuel and is slow (96) the starting line because it depends on learning—a gradual (97) —instead of instinct. Plenty of other species are able to learn, and one of the things they’ve apparently learned is when to (98) .
Is there an adaptive value to (99) intelligence That’s the question behind this new research. I like it. Instead of casting a wistful glance (100) at all the species we’ve left in the dust I.Q. wise, it implicitly asks what the real (101) of our own intelligence might be. This is (102) the mind of every animal I’ve ever met.
Research on animal intelligence also makes me wonder what experiments animals would (103) on humans if they had the chance. Every cat with an owner, (104) , is running a small-scale study in operant conditioning, we believe that (105) animals ran the labs, they would test us to (106) the limits of our patience, our faithfulness, our memory for terrain. They would try to decide what intelligence in humans is really (107) , not merely how much of it there is. (108) , they would hope to study a (109) question. Are humans actually aware of the world they live in (110) the results are inconclusive.

A．outside

B．on

C．by

D．across
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多项选择题

证券公司的主要业务包括( )。

A．推销政府债券

B．推销企业债券

C．推销股票

D．充当企业财务顾问

E．办理证券资金清算
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