With the world’s population estimated to grow from six to nine billion by 2050, researchers, businesses and governments are already dealing with the impact this increase will have on everything from food and water to infrastructure (基础设施) and jobs. Underlying all this (1) will be the demand for energy, which is expected to double over the next 40 years.Finding the resources to meet this demand in a (2) sustainable way is the cornerstone (基石) of our nation’s energy security, and will be one of the major (3) of the 21st century. Alternative forms of energy—bio-fuels, wind and solar, to name a few—are 4 being funded and developed, and will play a growing (5) in the world’s energy supply. But experts say that, even when (6) , alternative energy sources will likely meet only about 30% of the world’s energy needs by 2050.For example, even with (7) investments, such as the $93 million for wind energy development (8) in the American Recovery and Reinvestment Act, important alternative energy sources such as wind and bio-fuels (9) only about 1% of the market today.Energy and sustainability experts say the answer to our future energy needs will likely come from a lot of (10) —both traditional and alternative.A.stableB.solutionsC.significantD.roleE.progressF.marvelousG.includedH.growthI.exactlyJ.consistK.compriseL.competitionsM.combinedN.challengesO.certainly (5)处应填()
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编写函数fun,其功能是:计算n门课程的平均分,结果作为函数值返回。 例如,若有5门课程的成绩是:90.5,72,80,61.5,55,则函数的值为71.80。 注意:部分源程序给出如下。 请勿改动主函数main和其他函数中的任何内容,仅在函数fun的花括号中填入你编写的若干语句。 试题程序: #include <stdio.h> float fun(float * a, int n) void main() float score[30]=90.5, 72, 80, 61.5, 55), aver; aver=fun(score, 5); printf("\nAverage score is:% 5.2f\n", aver);
When we think of green buildings, we tend to think of new ones—the kind of high-tech, solar-paneled masterpieces that make the covers of architecture magazines. But the U.S. has more than 100 million existing homes, and it would be (1) wasteful to tear them all down and (2) them with greener versions. An enormous amount of energy and resources went into the construction of those houses. And it would take an average of 65 years for the (3) carbon emissions from a new energy-efficient home to make up for the resources lost by destroying an old one. So in the broadest (4) , the greenest home is the one that has already been built. But at the same time, nearly half of U.S. carbon emissions come from heating, cooling and (5) our homes, offices and other buildings. "You can’t deal with climate change without dealing with existing buildings," says Richard Moe, the president of the National Trust.With some (6) , the oldest homes tend to be the least energy-efficient. Houses built before 1939 use about 50% more energy per square foot than those built after 2000, mainly due to the tiny cracks and gaps that (7) over time and let in more outside air.Fortunately, there are a (8) number of relatively simple changes that can green older homes, from (9) ones like Lincoln’s Cottage to your own postwar home. And efficiency upgrades (升级) can save more than just the earth; they can help (10) property owners from rising power costs.A.accommodationsB.clumsyC.doubtfulD.exceptionsE.expandF.historicG.incrediblyH.poweringI.protectJ.reducedK.replaceL.senseM.shiftedN.supplyingO.vast (3)处应填()
Who has got a pen How much does one shirt cost
A. $6.00.
B. $6.50.
C.$12.00.
Walking, if you do it vigorously enough, is the overall best exercise for regular physical activity. It requires no equipment, everyone knows how to do it and it carries the (1) risk of injury. The human body is designed to walk. You can walk in parks or along a river or in your neighborhood. To get (2) benefit from walking, aim for 45 minutes a day, an average of five days a week.Strength training is another important (3) of physical activity. Its purpose is to build and (4) bone and muscle mass, both of which shrink with age. In general, you will want to do strength training two or three days a week, (5) recovery days between sessions.Finally, flexibility and balance training are (6) important as the body ages. Aches and pains are high on the list of complaints in old age. The result of constant muscle tension and stiffness of joints, many of them are (7) , and simple flexibility training can (8) these by making muscles stronger and keeping joints lubricated (润滑). Some of this you do whenever you stretch. If you watch dogs and cats, you’ll get an idea of how natural it is. The general (9) is simple: whenever the body has been in one position for a while, it is good to (10) stretch it in an opposite position.A.allowingB.avoidableC.brieflyD.componentE.determinedF.helpingG.increasinglyH.lowestI.maintainJ.maximumK.preventL.principleM.provokeN.seriouslyO.topic (4)处应填()