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php是一种__语言?

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PHP 代码在服务器上执行,结果以___形式返回给浏览器

php是运行在服务端的语言?

A. 对
B. 错

Unit 9Nuclear Energy -The Green Solution1 The United States with less than 5% of the world's population consumes roughly 25% of theworld's energy. Some might argue that this isegregious, while others would say that it is simplya yardstick by which the world's largest economy is measured. But forwhatever the reason for our vast consumption of energy, the fact remainsthat in order to consume you first have to produce. Yet most of ourenergy comes from burning fossil fuels which is associated with a numberof problems.2 Burning vast amounts of fossil fuels in this county alone dumpsmillionsof pounds of earth warming greenhouse gases into,what appears, a fragileatmosphere, every day. Just warming up the atmosphere a couple of degreeson average has significant impact. We need look no further than last year'shurricane season which was the worst on record.3 We must also not forgetits close cousin, smog pollution, which adds to respiratory problems andother health conditions, not tomention the visual blight hanging over our cities as well.4 In addition,have you filledyour tank recently? Paid the heating bill? Thecostof all fossil fuels, even coal has increased significantly. As other emergingeconomies suchas China and Indiaviefor ever more limited resources, allbets are that the costs will continue to climb over the long haul.5 .Moreover,as we import most of our oil nowadays, we are increasinglyheld hostage to an unstable supply from a number of countries that we, forwhateverreasons, areincreasingly unpopular with. The end game? If oursupply ofoil isnot first arbitrarily cut off, as it becomes increasingly scarcethe price will rise until our growth is strangled. In either case we will feel impelled to engage in war withother rising powers to secure our supplies.6The bottom line: Fossil fuels are not only hazardous to our health (and the planet's) but may in factbe hazardous to the American way of life.7 But if energy is the lifeblood of our economy what are we to do?Explore wind or solar energy?While anything we can do other than consume fossil fuels will help, these sources of energy are relativelydiffuse and inconsistent. In other words, their “cost to calorie”ratios are not efficient and they are notalways dependable. As James Kunstler points out in his intriguing book The Long Emergency, one of ourbest options out of these dilemmas is to do an“Apollo Project”type effort to develop additional, newnuclear energy capability.As it turns out, it just may be the greenest, viable alternate we have.8The US currently produces about 20% of its electrical power from nuclear power. The advantagesare that there are no greenhouse emissions into the atmosphere, no visual pollution, it is relatively costeffective, quiet and we have sufficient supply of uranium here at home for the foreseeable future toprovide for a major portion of our energy needs.9 However, there are new technologies in this field that, like the cavalry, have come to our rescueand none too soon. First,there is a new class of nuclear reactors that have their nuclear fuel sostructured that they cannot do a melt down. Turn off the cooling to this new nuclear reactor and it onlygets a bit hotter. This is no big deal. Turn the cooling back on and it runs more efficiently. Okay, onedown.But what about all that radioactive spent reactor fuel? Let's see if we can put some perspectiveon it. If you gathered all the spent nuclear fuel in this country under one roof it would fill a typicalhigh school gym. Not too unmanageable.Moreover, the spent fuel is encapsulated in super strong glassbeads, which in turn are embedded into hardened concrete inside steel drums. This makes the wasteproduct "transportable” and is designed to withstand the elements for 10,000 years. Nevertheless, evenin its tomb it is still relativity radioactive. Most of these drums are stored in water as radiation cannotpenetrate more than about three feet of water.However, no one seems anxious to have it in their backyards. A political hot potato to be sure.10 But while our politicians do not have the answer, the earth does. The answer lies in the bottom ofthe Marianas Trench in the Pacific. It is the deepest place in the ocean (over seven miles) and one ofthe fastest moving subduction plates on earth. If the drums of waste were placed in the bottom of thetrench, they would,within a few hundred years, be swallowed up into the bowels of the earth andblend into the earth's core where heat and pressure (caused in part by radioactive substances containedwithin the earth) are rendered insignificant.ll Given the current geopolitical situationwhich only seems to be working to our disadvantage,limitedresources for cheap fossil fuels, not to mention the environmental impact we are starting to experience, it istime we took drastic measures to get us off our fossil fuel addition. Let's hope we are not too late.(851 words)Multiple ChoicesChoose the best answer from the four choices given below according to the text.1. According to the author, what was the cause of last year's hurricane in America?A. Burning fossil fuels.B. Fragile atmosphere.c. Temperature.D. Smog pollution.2. What will be the result of America's competing with newly-emerging economic powers forlimited resources and importing oil from countries that are not on good terms?A. The cost of energy will continuously increase.B. The development in America will be largely restricted.C. America will be at war to obtain energy supplies.D. All of the above.3. Which of the following is NOT an advantage of nuclear energy?A. It does not have greenhouse emissions.B. It does not produce noise.C. It is pollution-free.D. It is relatively cost effective.4. Which of the following statements is true about dealing with the nuclear waste?A. The nuclear waste can be stored in a high school gym.B. The nuclear waste will not be radioactive in glass beads.C. The politicians will find out a definite solution to it.D. The glass beads containing nuclear waste can be put in the ocean trench.5. What is the author's attitude towards developing additional, new nuclear energy capability?A. Exaggerated.B. Supportive.C. Indifferent.D. Worried.

XAMPP可以在哪些操作系统下安装使用?

A. Windows
B. Linux
C. Solaris
D. Mac OS

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