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问题 填空题

如图所示是小红同学检查视力时的情景．小红同学的像到平面镜的距离为______m，小红同学看到镜中视力表上的“E”字的开口向下，则实际视力表中“E”字的开口应______．

答案

由图可知，小红到平面镜的距离为2.5m-0.4m=2.1m，

由平面镜成像特点：像与物到镜面距离相等，可知小红同学的像到平面镜的距离也为2.1m；

像和物关于镜面对称，物体朝上，像也朝上，物体朝下，像也朝下，所以E字的朝向是相同的．

故答案为：2.1；向下．

单项选择题

In the 1960s, many young Americans were dissatisfied with American society. They wanted to end the Vietnam War and to make all of the people in the US equal. Some of them decided to "drop out" of American society and form their own societies. They formed utopian communities, which they called "communes", where they could follow their philosophy of "do your own thing". A group of artists founded a commune in southern Colorado called "Drop City". Following the ideas of philosopher and architect Buckminster Fuller they built dome shaped houses from pieces of old cars. Other groups, such as author Ken Kesey’s Merry Pranksters, the followers of San Francisco poet Steve Gaskin, and a group that called itself the Hog Farm, lived in old school houses and traveled around the United States. The Hog Farm became famous when they helped organize the Woodstock Rock Festival in 1969. Steve Gaskin’s followers tried to settle down on a farm in Tennessee, but they had to leave when some members of the group were arrested for growing marijuana.
Not all communes believed in the philosophy of "do your own thing", however. Twin Oaks, a commune founded in Virginia in the late 1960s, was based on the ideas of psychologist B. F. Skinner. The people who lived at Twin Oaks were carefully controlled by Skinner’s "conditioning" techniques to do things that were good for the community. In 1972, Italian architect Paolo Soleri began to build Arcosanti, a utopian city Arizsona where 2,500 people will live closely together in one large building called an " archeology". Soleri believes that people must live closely together so that they will all become one.

Where did the members of the Hog Farm commune live

A．In dome shaped house.
B．In old school houses.
C．On a farm in Tennessee.
D．In an archeology in Arizona.
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单项选择题 A1/A2型题

女性，20岁。因外伤致第4、5颈椎骨折并发颈髓损伤，四肢呈弛缓性瘫痪，高热40℃，持续数日不降。应采取何种降温方法（）

A.口服A、P、C

B.冬眠疗法

C.使用抗生素

D.物理降温

E.以上都不是
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