试题与答案

美国的单位面积建筑能耗为每年187()。 A.瓦特 B.瓦特/平方米 C.千瓦时/平

题型:单项选择题

题目:

美国的单位面积建筑能耗为每年187()。

A.瓦特

B.瓦特/平方米

C.千瓦时/平方米

D.千焦/平方米

答案:

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参考答案:C解析:中心线与被照体局部边缘相切为切线方向摄影。前后方向为中心线由被照体前方投射向后方。后前方向为中心线由被照体后方投射向前方。冠状方向表示中心线左、右或右、左方向投射。轴方向是指中心线...

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题型:阅读理解

Ⅲ 阅读(共两节,满分40分)

.第一节:阅读理解(共15小题;每小题2分,满分30分)

A

Today I’ll be talking about the invention of the camera and photography. The camera is often thought to be a modern invention, but as early as 1727, a German physicist discovered that light darkens silver salt. Used as a camera, a big box was set up, and a small hole was cut in one side to let the light in; he made temporary pictures on the salt. Silver salt is still the base of the photographic film today. Then a French scientist made the first permanent picture by using a special piece of metal which was covered with silver salt. A photograph he made in 1826 still exists.

The painter De Gear improved the process by covering the metal also with placing the common salt which we can eat. This was in 1839, the official date of beginning of photographs. But the problem was the printing of the photographs. And it wasn’t until other scientists developed the kind of photographic paper we now use that good prints were possible and photography became truly modern. In the 1870’s, Matthew Bradey was able to take his famous pictures in American Civil War. In the 20’s of this century, Georges Mann of the United States simplified film developing (冲洗), and Dr Edward Lane invented the so—called ‘Instant Camera’ which uses self—developing film. If we say photography came into existence in 1839, it follows that it took more than 100 years for the camera to reach its present condition of technical refinement(密度).

1. What discovery was the basis of photography?

A. Light darkens silver salt.                     B. Light darkens natural salt.

C. Light darkens silver.                         D. Light darkens self--developing film

2. How was the first permanent picture made?

A. By making use of special paper.               B. By adding common salt to silver salt.

C. By giving a slight colour to the silver salt.       D. By using a special piece of metal.

3. What does the speaker regard as the official date of beginning of photography?

A. 1727          B. 1826            C. 1839            D. 1870

4. According to the speaker why is Matthew Bradey remembered today?

A. He was a soldier.                   B. He took war photographs.

C. He painted portraits.                 D. He designed a portable camera.

5. What did Doctor Edward Lane invent?

A. A cheap process of developing film at home.

B. A new kind of film.

C. An automatic printer.

   D. An ‘instant camera’ that develops its own film.

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