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问题 问答题 简答题

压支架有哪些工作特性？

答案

参考答案：

（1）液压支架的初撑力小于额定的工作阻力时具有增阻性

（2）液压支架的初撑力等于额定的工作阻力时具有恒阻性

（3）液压支架的初撑力大于额定的工作阻力时具有可缩性

单项选择题

根尖囊肿的特征性诊断（）。

A.牙髓无活力

B.X线示根尖周透射区周边有白线围绕

C.根管内淡黄透明囊液

D.囊液中见到胆固醇结晶

E.根尖周骨质膨隆
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单项选择题

Research on animal intelligence always makes us wonder just how smart humans are. (1) the fruit-fly experiments described by Carl Zimmer in the Science Times. Fruit flies who were taught to be smarter than the average fruit fly (2) to live shorter lives. This suggests that (3) bulbs burn longer, that there is a(n) (4) in not being too bright.

Intelligence, it (5) , is a high-priced option. It takes more upkeep, burns more fuel and is slow (6) the starting line because it depends on learning — a(n) (7) process — instead of instinct. Plenty of other species are able to learn, and one of the things they’ve apparently learned is when to (8) .

Is there an adaptive value to (9) intelligence That’s the question behind this new research. Instead of casting a wistful glance (10) at all the species we’ve left in the dust I.Q.-wise, it implicitly asks what the real (11) of our own intelligence might be. This is (12) the mind of every animal we’ve ever met.

Research on animal intelligence also makes us wonder what experiments animals would (13) on humans if they had the chance. Every cat with an owner, (14) , is running a small-scale study in operant conditioning. We believe that (15) animals ran the labs, they would test us to (16) the limits of our patience, our faithfulness, our memory for locations. They would try to decide what intelligence in humans is really (17) , not merely how much of it there is. (18) , they would hope to study a(n) (19) question: Are humans actually aware of the world they live in (20) the results are inconclusive.

14（）

A. by chance

B. in contrast

C. as usual

D. for instance
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