网友您好， 请在下方输入框内输入要搜索的题目：
题目内容
（请给出正确答案）
单选题
A
It affects the growth of trees.
B
It has been increasing since the Ice Age.
C
It is determined by the chemicals in the air.
D
It follows a certain cycle.
参考答案
参考解析
解析：
细节题。录音明确提到“the sun has cycles”，最后说明“The scientists concluded that solar wind activity must follow the same cycle.”可推断“Solar wind activity follows a certain cycle”。故选D。
【录音原文】
You can tell the age of a tree by counting its rings. But these records of a tree’s life really say a lot more. Scientists are using tree rings to learn what’s been happening on the sun’s surface for the last 10,000 years. Each ring represents a year of growth. As a tree grows, it adds a layer to its trunk, taking up chemical elements from the air. By looking at the elements in the rings from a given year, scientists can tell what elements were in the air that year. Doctor Stevenson is analyzing one element: carbon 14 in rings from both living and dead trees. Some of the rings go back almost 10,000 years to the end of the Ice Age. When Stevenson followed the carbon 14 trail back in time, he found carbon 14 levels change with the intensity of solar burning. You see, the sun has cycles. Sometimes it burns fiercely, at other times it’s relatively calm. During the sun’s violent periods it throws off charged particles in fast moving streams called solar winds. The particles interfere with the formation of carbon 14 on Earth. When there’s more solar wind activity, less carbon 14 is produced. Ten thousand years of tree rings show that the carbon 14 level rises and falls about every 420 years. The scientists concluded that solar wind activity must follow the same cycle.
Questions 1 to 3 are based on the passage you have just heard.
1. What’s the purpose of the scientists in studying tree rings?
2. What affects the amount of carbon 14 on Earth?
3. What do we learn from the passage about solar wind activity?
细节题。录音明确提到“the sun has cycles”，最后说明“The scientists concluded that solar wind activity must follow the same cycle.”可推断“Solar wind activity follows a certain cycle”。故选D。
【录音原文】
You can tell the age of a tree by counting its rings. But these records of a tree’s life really say a lot more. Scientists are using tree rings to learn what’s been happening on the sun’s surface for the last 10,000 years. Each ring represents a year of growth. As a tree grows, it adds a layer to its trunk, taking up chemical elements from the air. By looking at the elements in the rings from a given year, scientists can tell what elements were in the air that year. Doctor Stevenson is analyzing one element: carbon 14 in rings from both living and dead trees. Some of the rings go back almost 10,000 years to the end of the Ice Age. When Stevenson followed the carbon 14 trail back in time, he found carbon 14 levels change with the intensity of solar burning. You see, the sun has cycles. Sometimes it burns fiercely, at other times it’s relatively calm. During the sun’s violent periods it throws off charged particles in fast moving streams called solar winds. The particles interfere with the formation of carbon 14 on Earth. When there’s more solar wind activity, less carbon 14 is produced. Ten thousand years of tree rings show that the carbon 14 level rises and falls about every 420 years. The scientists concluded that solar wind activity must follow the same cycle.
Questions 1 to 3 are based on the passage you have just heard.
1. What’s the purpose of the scientists in studying tree rings?
2. What affects the amount of carbon 14 on Earth?
3. What do we learn from the passage about solar wind activity?
更多 “单选题A It affects the growth of trees.B It has been increasing since the Ice Age.C It is determined by the chemicals in the air.D It follows a certain cycle.” 相关考题
考题
His sister left home in 1998, and _______since.A. has not been heard of B. has not been heard ofC. had not heard of D. has not heard of
考题
There has been housing development on a massive ________ since 1980.A rangeB scaleC degreeD level
考题
It has been ten years now since the Labor Party came to ( ).
A、chargeB、forceC、powerD、control
考题
Tom () since he lost his job three weeks ago.
A、has employedB、was unemployedC、had been unemployedD、has been unemployed
考题
Of the fllowing sectors in Britain,()has experienced spectacular growth since the end of World War I.
A、agricultureB、the energy industryC、the service sectorD、the manufacturing industry
考题
_____, water turns into ice.A、When freezingB、When frozenC、When it has been frozenD、When freezes to it
考题
Which of the following statements is NOT true?A) World population is increasing at a rate of 150 per minute.B) Lower death rates also contribute to world population growth.C) The population of Columbia has been doubling every year for 21 years.D) The United States is usually doubling its population about every 87 years.
考题
His sister left home in 1998, and since. A. had not been heard of B. has not been heard ofC. had not heard of D. has not heard of
考题
______is the process by which the position of the vessel at any moment is found by applying the last well-determined position to the run that has been made since, using for this purpose the ship’s course and the distance being those indicated by log.A.dead reckoningB.dead weightC.dead slow aheadD.dead slow astern
考题
Racial discrimination has still___________ in some parts of the U.S.A. since itafter the Civil War.A.been existed; has been done away
B.existed; has been done away with
C.been existed; has been done away with
D.existed; was done away with
考题
His sister left home in 1998，and（）since．
A.had not been heard of
B.has not been heard of
C.had not heard of
D.has not heard of
考题
问答题Pollution 1)Pollution is a problem because man, in an increasingly populated and industrialized world，is upsetting the environment in which he lives. 2) Many scientists maintain that one of man's greatest errors has been to equate growth with advancement. 3) Now “growth” industries are being looked on with suspicion incase their side effects damage the environment and disrupt the relationship of different forms of life. 4) The growing population makes increasing demands on the world’s fixed supply of air, water and land. 5) This rise in population is accompanied by the desire of more and more people for a better standard of living. 6) The problem has been causing increasing concern to living things and their environment.
考题
问答题Pollution is a problem because man, in an increasingly populated and industrialized world, is upsetting the environment in which he lives. Many scientists maintain that one of man’s greatest errors has been to equate growth with advancement. Now “growth” industries are being looked on with suspicion in case their side effects damage the environment and disrupt the relationship of different forms of life, the growing population makes increasing demands on the world’s fixed supply of air, water and land.
考题
单选题Increasing differential pressure of an oil filter indicates that （）A
it is dirtyB
it is leakyC
it has been renewedD
all the above
考题
单选题A
It affects the growth of trees.B
It has been increasing since the Ice Age.C
It is determined by the chemicals in the air.D
It follows a certain cycle.
考题
单选题Since the Second World War, most urban growth in the United States has occurred on the outskirts of existing metropolitan areas.A
counties B
edges C
streets D
intersections
考题
问答题Although the American economy has transformed itself over the years, certain issues have persisted since the early days of the republic. One is the continuing debate over the proper role for government in what is basically a marketplace economy. An economy based on free enterprise is generally characterized by private ownership and initiative, with a relative absence of government involvement. However, government intervention has been found necessary from time to time to ensure that economic opportunities are fair and accessible to the people, to prevent flagrant abuses, to dampen inflation and to stimulate growth.Ever since colonial times, the government has been involved, to some extent, in economic decision-making. The federal government, for example, has made huge investments in infrastructure, and it has provided social welfare programs that the private sector was unable or unwilling to provide. In a myriad of ways and over many decades, the government has supported and promoted the development of agriculture.
考题
单选题（）is the process by which the position of the vessel at any moment is found by applying the last well-determined position to the run that has been made since，using for this purpose the ship’s course and the distance being those indicated by log.A
dead reckoningB
dead weightC
dead slow aheadD
dead slow astern
考题
单选题Hannah finished building her new all-purpose projects room last year, and she has been working in the room ever since.A
and she has been working in the room ever sinceB
and since that time she has worked thereC
where always since she worksD
she has been working in that room ever sinceE
and since then is working there
考题
问答题Pollution is a problem because man, in an increasingly populated and industrialized world, is upsetting the environment in which he lives. Many scientists maintain that one of man’s greatest errors has been to equate growth with advancement. Now “growth” industries are being looked on with suspicion in case their side effects damage the environment and disrupt the relationship of different forms of life. The growing population makes increasing demands on the world’s fixed supply of air, water and land. This rise in population is accompanied by the desire of more and more people for a better standard of living. Thus still greater demands for electricity, water and goods result in an ever increasing amount of waste material to be disposed of.The problem has been causing increasing concern to living things and their environment. Many believe that man is not solving these problems quickly enough and that his selfish pursuit of possessions takes him past the point of no return before be fully appreciates the damage.
考题
单选题It has been ten years since the Labour Party came into（）in that country.A
controlB
forceC
powerD
charge
考题
单选题Which of the following sentences is INCORRECT?A
His father has been dead for six years.B
His father died six years ago.C
It’s six years since his father had died.D
It has been two years since his father’s death.
考题
单选题Others argue that since the earth has endured a long string of ice ages in the last two million to three million years, any warming is（）to be temporary.A
seemedB
likelyC
tendedD
possible
热门标签
最新试卷
