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【简答题】
在做“探究凸透镜成像规律”的实验时： （1）如图甲所示，一束平行于凸透镜主光轴的光线经过凸透镜后，在上形成了一个最小、最亮的光斑。由图甲可知，凸透镜对光线具有________作用，该凸透镜的焦距是________cm。 （2）小明将该凸透镜放在光具座上进行实验，蜡烛、凸透镜、在光具座上的位置如图乙所示，其中明显还需要调整的是，使、凸透镜、三者中心在_______________。调整后，在上恰好得到一个清晰的蜡烛的像，请你详尽地描述这个像的特点：__________________。 （3）此时，小明把自己的近视眼镜放在蜡烛和凸透镜之间且靠近凸透镜的位置，结果上原来清晰的像变模糊了，若不改变蜡烛和凸透镜的位置，向_______凸透镜的方向移动（填 “远离”或“靠近”），使蜡烛的像变清晰。此实验说明近视眼配戴合适的近视眼镜能矫正视力的原因是______________________。
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【单选题】I n Paras. 6 — 13, three methods of animal protection are mentioned,which of the following is not correct?
A.
Captive breeding
B.
Actions of the animal rights group of PETA
C.
Vegetarianism
D.
Wildlife conservation law
【单选题】Which of the following about the controlling idea is not true?
A.
A paragraph is a sentence or group of sentences that support one main idea. That ’ s what we call the “controlling idea” because it controls what happens in the rest of the paragraph.
B.
The information in each paragraph must be related to that idea.
C.
I t is about the most important idea that you are trying to convey to your reader in a paragraph.
D.
I t is always the first sentence.
【单选题】Remember not to ____ when you enter the room.
A.
look up
B.
look round
C.
look into
D.
look through
【简答题】“When your mother scolds you, you can look elsewhere and think about other things. Just ignore her words. But remember: such a tough attitude cannot be used often.” These words are from a series of ca...
【单选题】Which of the following is true about c ollectivism ? A ) T ies between individuals are not strong. B) P eople are expected to take care of themselves. C) I t is believed that if each person takes care...
A.
a
B.
b
C.
c
D.
d
E.
e
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