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Colors There are two ways to create colors in a photograph. One method, called additive, starts with three basis colors and adds them together to produce some other colors. The second method, called subtractive, starts with white light (a mixture 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), magents (a purplish pink), and yellow; these are the pigments or dyes that absorb red, green and blue wavelengths, respectively, thus subtracting them form white light. These dye colors are the complementary colors to the three additive primaries of red, green and blue. Properly combined the subtractive primaries and 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 closest in meaning to the phrase "passes on" as used in line 14
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阅读下面的短文，文中有15处空白，每处空白给出4个选项。请根据短文的内容，从4个选项中选择1个最佳答案。Reading Reading involves looking at graphic symbols and formulating mentally the sounds and ideas they represent. Concepts of reading have changed substantially over the centuries. During the 1950’s, and 1960’s especially, increased attention has been devote (51) defining and describing the reading process. (52) specialists agree that reading (53) a complex organization of higher mental (54) , they disagree (55) the exact nature of the process. Some experts, who regard language primarily as a code using symbols to represent sounds, (56) reading as simply the decoding of symbols into the sounds they stand (57) . These authorities (58) that meaning, being concerned with thinking, must be taught independently of the decoding process. Others maintain that reading is inextricably related to thinking, and that a child who pronounces sounds without (59) their meaning is not truly reading. The reader, (60) some, is not just a person with a theoretical ability to read but one who (61) reads. Many adults, although they have the ability to read have never read a book in its entirety. By some experts they would not be (62) as readers. Clearly, the philosophy, objectives, methods and materials of reading will depend on the definition one uses. By the most inclusive and satisfactory definition, reading is the ability to (63) the sound-symbol code of the language, to interpret meaning for various purposes, at various rates, and at various levels of difficulty, and to do (64) widely and enthusiastically. (65) , reading is the interpretation of ideas through the use of symbols representing sounds and ideas.
男性患者，58岁，上腹疼痛，反酸，内镜检查发现，十二指肠降段、水平段及空肠多发性溃疡，抑酸治疗效果不佳。 进一步应做的检查是
卤水依其色泽分为红卤水、白卤水和盐水卤三类。( )
下面有3篇短文，每篇短文后有5道题，每题后面有4个选项。请仔细阅读短文，并根据短文回答其后面的问题，从4个选项中选择1个最佳答案。第一篇The treasure Locked away in a vault underneath the presidential palace in Kabul is a priceless treasure which is at the mercy of the American bombardment and the Taleban’s spite and greed. Art experts want the UN to rescue this 2, 100-year-old hoard of gold antiquities, called the Treasure of Bactria, before it is destroyed or the Tableban melt it down. What is remarkable is that the 20,000 or more gold statues, necklaces and ornaments set with precious stones have survived for so long in a city scarred by years of war. Rumors swirl around the bazaars of the capital about what the Taleban has done with the treasure, which was excavated from a royal burial site in northern Afghanistan by a Soviet team during the Soviet Union’s occupation. The team described how the 20,000 gold pieces included statues, necklaces, dress ornaments, hairpins and buckles deco rated with precious stones. There were also plaques decorated with jewels and a crown covered in pearls and turquoise. The treasure survived until its excavation in 1978. After that, the country’s former President Najibullah, sealed it in many trunks and hid them in a vault and protected by a steel door shut by seven locks with keys held by seven different people. At least three of the key holders are now dead, Mr. Najibullah included. Another popular fable circulating in Kabul is that the Russians have a duplicate set of the seven keys. Others claim that a traitor team of Soviet troops broke into the vault in the last hours before they abandoned Kabul and replaced some of the treasures with fakes. Now all anyone can say for sure is that the treasure was last seen and inspected by international archaeologists in 1993. when the safe was opened to clarify rumors that the Afghans had sold it. UNESCO says that it has given the Americans a map so that its bombers can avoid vital cultural sites, which include the vault in the presidential palace and other places, where other museum treasures are stored. There are many in Kabul who say the Taleban have already handed the treasure to Osama Bin Laden. Robert Kluyver, of the Society for the Preservation of Afghanistan’s Cultural Heritage, was told recently that Bin Laden had arranged for it to be smuggled across the mountains to Pakistan in March where dealers awaited his orders to sell it. Where are the treasures now according to the writer
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