填空题Glucose can be completely broken down into carbon dioxide and water when oxygen is present in the process called aerobic respiration.____

第1题

The most effective way of applying carbon dioxide from a portable extinguisher to a fire is by ______．A.Forming a cloud cover over the flamesB.Directing the gas at the base of the flames in a slow sweeping motionC.Discharging the carbon dioxide into the heart of the flamesD.Bouncing the discharge off an adjacent bulkhead just above the burning surface

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第2题

______, as the chemical extinguisher agent, should be used for an electric fire.A.dry chemical or foamB.foam or soda acidC.carbon dioxide or foamD.carbon dioxide or dry chemical

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第3题

Passage 2 If the population of the earth goes on increasing at its present rate, there will eventually not be enough resources left to sustain life on the planet. By the middle of the 21st century, if present trends continue, we will have used up all the oil that drives our cars, for example. Even if scientists develop new ways of feeding the human race, the crowded conditions on earth will make it necessary for us to look for open space somewhere else. But none of the other planets in our solar system are capable of supporting life at present. One possible solution to the problem, however, has recently been suggested by an American scientist, Professor Carl Sagan. Sagan believes that before the earth's resources are completely exhausted it will be possible to change the atmosphere of Venus and so create a new world almost as large as earth itself. The difficulty is that Venus is much hotter than the earth and there is only a tiny amount of water there. Sagan proposes that algae organisms, which can live in extremely hot or cold atmospheres and at the same time produce oxygen, should be bred in conditions similar to those on Venus. As soon as this has been done, the algae will be placed in small rockets. Spaceships will then fly to Venus and fire the rockets into the atmosphere. In a fairly short time, the algae will break down the carbon dioxide into oxygen and carbon. When the algae have done their work, the atmosphere will become cooler, but before man can set foot on Venus it will be necessary for the oxygen to produce rain. The surface of the planet will still be too hot for men to land on it but the rain will eventually fall and in a few years something like earth will be reproduced on Venus. On Venus there is a lot of__________.A. water B. carbon dioxide C. carbon monoxide D. oxygen

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第4题

An Essential Scientific ProcessAll life on the earth depends upon green plants. Using sunlight, theplants produce their own food. Then animals feed upon the plants. They take inthe nutrients the plants have made sted. But that’s not all.Sunlight also helps a plant produce oxygen. Some of the oxygen is used by theplant, but a plant usually produces me oxygen than it uses. The excess oxygenis necessary f animals other ganisms to live.The process of changing light into food oxygen is calledphotosynthesis. Besides light energy from the sun, plants also use water carbon dioxide. The water gets to the plant through its roots. The carbondioxide enters the leaves through tiny openings called stomata. The carbondioxide travels to chloplasts, special cells in the bodies of green plants.This is photosynthesis takes place. Chloplasts contain the chlophyllsthat give plants their green col. The chlophylls are the molecules thattrap light energy. The trapped light energy changes water carbon dioxide toproduce oxygen a simple sugar called glucose.Carbon dioxide oxygen move into out of the stomata. Watervap also moves out of the stomata. Me than 90 percent of water a planttakes in through its roots escapes through the stomata. During the daytime, thestomata of most plants are open. This allows carbon dioxide to enter the leavesf photosynthesis. As night falls, carbon dioxide is not needed. The stomataof most plants close. Water loss stops.If photosynthesis ceased, there would be little food other ganicmatter on the earth. Most ganisms would disappear. The earth’s atmospherewould no longer contain oxygen. Photosynthesis is essential f life on ourplanet.词汇：nutrient n.营养物 ganism n.生物体，有机体carbon dioxide n.二氧化碳chloplast n.叶绿体molecule n.分子vap n.水蒸气oxygen n.氧气 photosynthesis n.光合作用chlophyll n.叶绿素glucose n.葡萄糖cease v.停止注释：1.Then animals feed upon the plants.动物以植物为食。练习：5.Another good title f this passage would beA.Oxygen Carbon Dioxide.B.Plants Their Roots.C.How Photosynthesis Wks.D.Why Our Earth Needs Water.

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第5题

An Essential Scientific ProcessAll life on the earth depends upon green plants. Using sunlight, theplants produce their own food. Then animals feed upon the plants. They take inthe nutrients the plants have made sted. But that’s not all.Sunlight also helps a plant produce oxygen. Some of the oxygen is used by theplant, but a plant usually produces me oxygen than it uses. The excess oxygenis necessary f animals other ganisms to live.The process of changing light into food oxygen is calledphotosynthesis. Besides light energy from the sun, plants also use water carbon dioxide. The water gets to the plant through its roots. The carbondioxide enters the leaves through tiny openings called stomata. The carbondioxide travels to chloplasts, special cells in the bodies of green plants.This is photosynthesis takes place. Chloplasts contain the chlophyllsthat give plants their green col. The chlophylls are the molecules thattrap light energy. The trapped light energy changes water carbon dioxide toproduce oxygen a simple sugar called glucose.Carbon dioxide oxygen move into out of the stomata. Watervap also moves out of the stomata. Me than 90 percent of water a planttakes in through its roots escapes through the stomata. During the daytime, thestomata of most plants are open. This allows carbon dioxide to enter the leavesf photosynthesis. As night falls, carbon dioxide is not needed. The stomataof most plants close. Water loss stops.If photosynthesis ceased, there would be little food other ganicmatter on the earth. Most ganisms would disappear. The earth’s atmospherewould no longer contain oxygen. Photosynthesis is essential f life on ourplanet.词汇：nutrient n.营养物 ganism n.生物体，有机体carbon dioxide n.二氧化碳chloplast n.叶绿体molecule n.分子vap n.水蒸气oxygen n.氧气 photosynthesis n.光合作用chlophyll n.叶绿素glucose n.葡萄糖cease v.停止注释：1.Then animals feed upon the plants.动物以植物为食。练习：4.This passage is primarily developed byA.explaining a process.B.telling a sty.C.comparing contrasting.D.convincing the reader of plants’ imptance.

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第6题

An Essential Scientific ProcessAll life on the earth depends upon green plants. Using sunlight, theplants produce their own food. Then animals feed upon the plants. They take inthe nutrients the plants have made sted. But that’s not all.Sunlight also helps a plant produce oxygen. Some of the oxygen is used by theplant, but a plant usually produces me oxygen than it uses. The excess oxygenis necessary f animals other ganisms to live.The process of changing light into food oxygen is calledphotosynthesis. Besides light energy from the sun, plants also use water carbon dioxide. The water gets to the plant through its roots. The carbondioxide enters the leaves through tiny openings called stomata. The carbondioxide travels to chloplasts, special cells in the bodies of green plants.This is photosynthesis takes place. Chloplasts contain the chlophyllsthat give plants their green col. The chlophylls are the molecules thattrap light energy. The trapped light energy changes water carbon dioxide toproduce oxygen a simple sugar called glucose.Carbon dioxide oxygen move into out of the stomata. Watervap also moves out of the stomata. Me than 90 percent of water a planttakes in through its roots escapes through the stomata. During the daytime, thestomata of most plants are open. This allows carbon dioxide to enter the leavesf photosynthesis. As night falls, carbon dioxide is not needed. The stomataof most plants close. Water loss stops.If photosynthesis ceased, there would be little food other ganicmatter on the earth. Most ganisms would disappear. The earth’s atmospherewould no longer contain oxygen. Photosynthesis is essential f life on ourplanet.词汇：nutrient n.营养物 ganism n.生物体，有机体carbon dioxide n.二氧化碳chloplast n.叶绿体molecule n.分子vap n.水蒸气oxygen n.氧气 photosynthesis n.光合作用chlophyll n.叶绿素glucose n.葡萄糖cease v.停止注释：1.Then animals feed upon the plants.动物以植物为食。练习：3.In the title, the term Essential Scientific Process refers toA.photosynthesis.B.the fmation of glucose.C.global warming.D.water getting to the roots of plants.

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第7题

Which two statements regarding the Policy Framework in Enterprise Manager (EM) are correct?（）A、Policy violations are prioritized as High, Medium, or Informational by category B、Policies can be disabled completely, or flagged as ignored, for the specified target C、Policies can be flagged as ignored, but never completely disabled, for the specified targetD、Policy violations must be corrected, otherwise the database will shut down until corrective action occurs

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