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问题 探究题

在甲、乙、丙、丁四个培养皿中分别放等量的棉花，再将相同数量(各100粒)的绿豆种子放在上面，在不同条件下进行培养。数日后记录种子萌发情况如下表。

(1)根据本实验，可得出的结论是：种子萌发需要_________。

(2)种子萌发后，如果继续培养几周，幼苗生长较好的应该是_________组。

(3)要证明“光照对种子萌发是否有影响”，在实验设计上可选用_________作对比。

(4)丙组中有7粒种子没有萌发，请你给一个合理的解释。__________________。

答案

(1)水分

(2)甲

(3)甲和丙

(4)胚不完整或已死亡

填空题

已知小圆的半径是r，大圆的半径是小圆的3倍，大圆的面积是（     ）。
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单项选择题

The nobler and more perfect a thing is, the later and slower it is becoming mature. A man reaches the mature (1) of his reasoning powers and mental faculties (2) before the age of twenty-eight; a woman at eighteen. And then, too, in the case of woman, it is the only reason of a sort--very mean in its (3) . That is why women remain children their whole life long; never seeing (4) but what is quite close to them, (5) fast to the present moment, taking appearance for (6) , and preferring (7) to matters of the first importance. For it is (8) his reasoning faculty that man does not live in the present only, (9) the brute, but looks about him and considers the past and the future; and this is the origin of (10) , as well as that of care and anxiety which so many people (11) Both the advantages and the disadvantages, which this (12) , are (13) in by the woman to a smaller extent because of her weaker power of reasoning. She may, in fact, be described as intellectually shortsighted, (14) , while she has an immediate understanding of what lies quite close to her, her field of (15) is narrow and does not reach to what is (16) ; so that things which are absent, or past, or to come, have much less effect upon women than upon men. This is the reason why women are inclined to be (17) and sometimes carry their desire to a (18) that borders upon madness. In their hearts, women think it is men’s business to earn money and theirs to spend it--if possible during their husband’s life, (19) , at any rate, after his death. The very fact that their husband hands them (20) his earnings for purposes of housekeeping strengthens them in this belief.

18（）

A.end

B.limit

C.span

D.length
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