____dropped a number of devices that would burst with a loud noise when they hit the

A.Number of available subscriber services

B.Number of successful call set-ups

C.Channel utilization

D.Number of unsuccessful call set-ups due to congestion

E.Number of dropped calls

A.Because they don’t think foxes are harmful．

B.Because they think fox hunting is cruel．

C.Because they think fox hunting is expensive．

D.Because they think the number of foxes has dropped a lot．

The statement "The decline leveled off four years ago" (Last line, paragraph 2 implies that ______.

A．the number of children at boarding schools dropped sharply tour years ago

B．many boarding schools had to close four years ago

C．the changing of the number of the pupils in the boarding school became level after a sharp declining four years ago

D．more and more parents tended to send their children to some private school other than the boarding ones

What has happened in Australia where plain packaging is implemented？

A.Premature death rates resulting from smoking have declined.

B.The number of smokers has dropped more sharply than in the UK.

C.The sales of tobacco substitutes have increased considerably.

D.Cigarette sales have been falling far more quickly than in the UK.

A.Traditional packet loss policy is tail-drop. When length of a queue reaches a maximum value, all new packets will be dropped.

B.In RED algorithm, each queue is set a pair of low and high limit values. When length of the queue is lower than the low limit, packets will not be droppeD.When the length exceeds the high limit, all packets will be droppeD.When the length is between low limit and high limit, packets will be dropped randomly.

C.Random number generated by WRED is based on priority. It introduces IP priority differentiated drop policy, so probability of dropping packets with high priority is small.

D.Currently, default congestion control for PTN device is Tail-Drop.

听力原文： (29)Cancer is the second leading cause of death after heart disease.

Death rates for both diseases are falling. But researchers say the rate for heart disease is falling faster. As a result, an American Cancer Society report shows that cancer now kills more Americans under the age of eighty-five than any other cause.

Some cancers can be prevented or treated, especially if found early. Cancer is the name for a group of diseases. All involve the uncontrolled growth and spread of cells that are not normal. Cell growth and division are controlled by genes. (30) Some cancers are linked to family genetics. Pollution and chemicals can also raise a person's risk of cancer.

The report shows that in recent years, cancer rates in the United States have dropped about one percent per year. Lung, colon, breast and prostate cancer make up more than half of all the cases. For men, prostate cancer is the most common. For women, it is breast cancer. Rates of both have continued to increase, but more slowly than in the past.

Smoking causes about one-third of all cancer deaths. Poor diet and a lack of exercise are blamed for another third in the United States.

(31) The American Cancer Society says cancer deaths worldwide could increase nearly one hundred percent in the next twenty years. Yet most could be avoided. The report calls tobacco use "the number one cause of cancer and the number one cause of preventable death throughout the world. "

Hepatitis and other infections will cause an estimated seventeen percent of new cancers worldwide this year. (32) Such cancers are especially common in developing countries, and many of these cases can also be prevented.

29．What is the first leading cause of death？

30.What can be learned about cancers from the passage？

31.What does the American Cancer Society say about cancer？

32.What do we learn about cancers in developing countries'？

(33)

A．Heart disease.

B．Cancer.

C．Smoking.

D．Poor diet.

听力原文： Scientists in the United States have reported some good news about the ozone in the atmosphere. Recent findings suggest that the destruction of ozone by pollution is slowing. Ozone is a form. of oxygen. Its presence above Earth protects us from radiation from the sun.

In one study, researchers examined information gathered by NASA space agency satellites and by equipment on Earth and said the atmosphere was losing about eight percent of the ozone layer per ten- year period since the late 1970s. In the last five years, though, that rate of loss has dropped by half. The atmosphere should start to gain ozone before long. A full recovery, however, is about 50 years away, as long as the Montreal Protocol remains in place.

That is an international treaty from 1987 to restore the ozone layer. The treaty restricts the use of a number of chemicals that destroy ozone, like chlorofiuorocarbons, or C-F-C's. Wide use of C-F-C's began in the 1930s. They became popular coolants in devices such as refrigerators and air conditioners. C-F-C's remain in the atmosphere for years.

The Montreal Protocol also restricts the use of methyl bromide, a chemical to kill insects. Farmers and shippers are the main users. Natural sources of methyl bromide include oceans and some plants. Scientists say the bromine gas it produces is 50 times more destructive to ozone than chlorine gas from C-F-C's.

(30)

A．The destruction process of ozone layer is slowing down.

B．The ozone layer has been destroyed seriously.

C．Ozone layer can protect us from strong radiation from the sun.

D．Ozone is produced by waste gas.

A.dropped down

B.dropped off

C.dropped in

D.dropped out

A.dropped in

B.took out

C.took in

D.dropped out

A.dropped in

B.moved away

C.dropped for

D.moved forward