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【简答题】
已知：在△ABC中，∠ACB=90°，AC=BC，现将一块边长足够大的直角三角板的直角顶点置于AB的中点O处，两直角边分别经过点B、C，然后将三角板绕点O按顺时针方向旋转一个角度反（0°＜a＜90°），旋转后，直角三角板的直角边分别与AC、BC相交于点K、H，四边形CHOK是旋转过程中三角板与△ABC的重叠部分（如图1所示）．那么，在上述旋转过程中： （1）如图1，线段BH与CK具有怎样的数量关系？四边形CHOK的面积是否发生变化？请说明你发现的结论的理由． （2）如图2，连接HK， ①若AK=12，BH=5，求△OKH的面积； ②若AC=BC=4，设BH=x，当△CKH的面积为2时，求x的值，并说出此时四边形CHOK是什么特殊四边形．
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【简答题】用描述法表示平面内不在第一与第三象限的点的集合为（ ）。
【单选题】Which could best be substituted for the word 'THIS' in the last sentence of the second paragraph?
A.
The search of Japan's Tokugawa shoguns for solvency.
B.
The unfairness of the tax structure in eighteenth-century Japan.
C.
The difficulty experienced by both individual samurai and the shogun himself in extricating themselves from debt.
D.
The difficulty of increasing government income by other means.
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A.
RIP Request message
B.
RIP Response message
C.
RIP Hello time message
D.
RIP Update message
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【单选题】Let’s have a ________ at that second game. I’ll ________ for you.
A.
look; see
B.
read; look
C.
watch; read
D.
look; read
【简答题】绝对黑体温度升高一倍时,其辐射能力最大值所对应的波长就变为原来的 。
【单选题】The case ______ a lot of things, ______ a second-hand watch.
A.
included; contained
B.
included; containing
C.
contained; included
D.
contained; including
【单选题】The viewers will have _____ second chance to watch Voice of China on _____ Channel 4 tonight.
A.
a; the
B.
the; the
C.
the; /
D.
a; /
【简答题】用描述法表示平面内不在第一与第三象限的点的集合为______．
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