题目内容

Why is the man feeling bad（）

A. He had no sleep last night.
B. He went to bed too late last night.
C. He woke up several times last night.

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—Must I hand in my paper today —No, you （）. You can hand it in tomorrow.

A. mustn’t
B. needn’t
C. can’t

What does the man ask about（）

A. The time of a film.
B. The price of a hotel room.
C. The phone number of the cinema.

建筑工程一切险的除外责任包括（）造成的损失。

A. 台风;
B. 暴雨引起地面下陷;
C. 雷电引起火灾;
D. 自然磨损

There are two ways to create colors in a photograph. One method, called addtive, starts with three basic colors and adds them together to produce some other color. The second method, called subtractive, starts with white light (a mixtu re of all colors in the spectrum) and, by taking away some or all other colors, leaves the one desired. In the additive method, separate colored lights combine to produce various other colors. The three additive primary colors are green, red and blue (each providing about one third of the wavelengths in the total spectrum). Mixed in varying proportions, they can produce all colors. Green and red light mix to produce yellow; red and blue light mix to produce magenta; green and blue mix to produce cyan. When equal parts of all three of these primary colored beams of light overlap, the mixture appears white to the eye. In the subtractive process colors are produced when dye (as in paint or color photographic materials) absorbs some wavelengths and so passes on only part of the spectrum. The subtractive primaries are cyan (a bluish green), magenta (a purplish pink) and yellow; these additive primaries or dyes that absorb red, green and blue wavelengths respectively, thus subtracting them from white light. These dye colors are the complementary colors to the three additive primaries of red, green, and blue. Properly combined, the subtractive primaries can absorb all colors of light, producing black. But, mixed in varying proportions, they too can produce any color in the spectrum. Whether a particular color is obtained by adding colored lights together or by subtracting some light from the total spectrum. The result looks the same to the eye. The additive process was employed for early color photography. But the subtractive method, while requiring complex chemical techniques, has turned out to be more practical and is the basis of all modern color films. Which of the following is NOT a pair of additive and subtractive prim ary colors

A. Yellow and blue.
B. Magenta and green.
C. Black and white.
D. Cyan and red.