关于脑动脉粥样硬化的描述，正确的是______ A．引起动脉瘤形成 B．引起脑血栓形

下列关于质点的说法中正确的是（　　）

A．凡轻小的物体皆可看作质点

B．研究地球绕太阳公转时可以将地球看作质点

C．只有体积很小的物体才能看作质点

D．研究某学生骑车姿势的变化时可以把学生和车看作质点

某集团公司为扩展业务，计划采购一批运输车辆，现有两种方案可供选择。第1方案是采购10辆进口车辆，每辆车辆的离岸价格是3万美元，海上运费和运输保险费为1500美元/辆，银行财务费率为5‰，外贸手续费率为1.5%，进口关税税率为22%，增值税的税率为17%，美元的银行牌价为每美元6.5元人民币，车辆的国内运杂费率为6000元/辆。假定其他税费暂不考虑。第2方案是采购14辆国产车辆才能达到同等效果，价格为20万元/辆，需要交纳购置税等费用2万元/辆。每车的车辆操作人员的平均工资为30000元/年，设备的使用寿命均为8年，8年内进口车辆和国产车辆均可行驶80万公里，8年后车辆报废，没有残值。在运营期间，每辆进口车的燃油成本、日常维护成本和大修成本合计为0.7元/km，每辆国产车的燃油成本、日常维护成本和大修成本合计为0.6元/km。上述财务数据中，除人工费、外汇汇率外，不存在价格扭曲现象，进口车辆的劳动力影子价格转换系数按1.2计算，国产车辆按1.0计算，影子汇率转换系数为1.08，社会折现率为10%。复利系数见表4。

从国民经济的角度，计算每公里综合经济成本。

阅读理解。

     Edmund Halley was an English scientist who lived over 200 years ago. He studied the observations of

comets(彗星) which other scientists had made. The orbit of one particular comet was a very difficult

mathematical problem. He could not figure it out. Neither could other scientists who dealt with such problem.

     However, Halley had a friend named Isaac Newton, who was a brilliant mathematician. Newton thought

he had already worked out that problem, but he could not find the papers on which he had done it. He told

Halley that the orbit of a comet had the shape of an ellipse  (椭圆形).

     Then Halley set to work. He figured out (解决, 计算出) the orbjts of some of the comets that had been

observed by scientists. He made a surprising discovery. The comets that had appeared in the years 1531, 1607,

and 1682 all had the same orbit. Yet their appearances had been 75 to 76 years apart.

     This seemed very strange to Halley. Three different comets followed the same orbit. The more Halley

thought about it, the more he thought that there had not been three different comets, as people thought. He

decided that they had simply seen the same comet three times. The comet had gone away and had come back

again.

     It was an astonishing idea! Halley felt certain enough to make a prediction (预言) of what would happen

in the future. He decided that this comet would appear in the year 1758. There were 53 years to go before

Halley's prediction could be tested.

     In 1758 the comet appeared in the sky. Halley did not see it, for he had died some years before. Ever since

then that comet had been called Halley's comet, in his honour.

1. Edmund Halley figured out the orbit of _____. [ ]

A. some different comets appearing several times

B. the same comet appearing at different times

C. three different comets appearing three times

D. several comets appearing at the same time

2. Halley made his discovery _____. [ ]

A. by doing experiments

B. by means of his own careful observation

C. by using the work of other scientists

D. by chance

3. Halley made a surprising, but correct prediction in the year _____. [ ]

A. 1704

B. 1705

C. 1706

D. 1707

4. This passage in general is about _____. [ ]

A. Halley and other scientists

B. the orbit of a comet

C. Newton and Halley

D. Halley and his discovery

5. Which of the following is TRUE? [ ]

A. Edmund Halley was an American scientist.

B. Halley made his discovery by doing experiments.

C. Isaac Newton was a famous mathematician.

D. The orbit of a comet had the shape of a triangle.

下列哪一项不属于半月板损伤之检查：

A．抽屉试验

B．重力试验

C．麦氏征

D．研磨提拉试验

E．交锁征

For years pediatricians didn’t worry much about treating hypertension in their patients. After all, kids grow so fast, it’s hard keeping up with their shoes size, let alone their blood pressure. Sure, hypertension in adults places them at greater risk of heart attack and stroke. But nobody likes the idea of starting youngsters on blood-pressure medicine they could wind up taking the rest of their lives. Who knows what previously unheard-of side effects could crop up after five or six decades of daily use

The rationale has been: kids grow out of so many things; maybe they’ll grow out of this too.

41．Now, though, comes word that high blood pressure can be destructive even in childhood.

42．Who is most at risk

Boys are more than girls, especially boys who are overweight. Their heart works so hard to force blood through extra layers of fat that its walls grow denser. Then, after decades of straining, it grows too big to pump blood very well.

43．How can you tell if yours are like the 670,000 American children ages 10 to 18 with high blood pressure

It’s not the sort of thing you can catch by putting your child’s arm in a cuff at the free monitoring station in your local grocery. You should have a test done by a doctor, who will consult special tables that indicate the normal range of blood pressure for a particular child’s age, height and sex.

44．About half the cases of hypertension stem directly from kids being overweight.

45．How can you do

You can keep your children from joining their ranks by clearing the junk food from your pantry and hooking you kids — the earlier the better — on healthy, attractive snakes like fruits (try freezing some grapes/or carrot sticks with salsa. ) Not only will they lower your children’s blood pressure: These foods will also boost their immune system and unclog their plumbing.

[A] And the problem is likely to grow. Over the past 30 years the proportion of children in the U. S. who are overweight has doubled, from 5% to 11% or 4.7 million kids.

[B] According to a recent report in the journal Circulation, 19 of 30 children with high blood pressure developed a dangerous thickening of the heart muscle that, in adults at least, has been linked to heart failure. “No one knows if this pattern holds true for younger patients as well, ” says Dr. Stephen Daniels, a pediatric cardiologist who led the study at Children’s Hospital Medical Center in Cincinnati, Ohio. “But it’s worrisome. ”

[C] Feed your children nutritious foods three times a day to keep his immune system healthy. Make sure the meals include all the food groups to ensure they are getting plenty of vitamins.

[D] Fortunately the abnormal thickening can be spotted by ultrasound. And in most case, getting that blood pressure under control — through weight loss and exercise or, as a last resort, drug treatment — allows the overworked muscle to shrink to normal size.

[E] If the doctor finds an abnormal result he will repeat the test over a period of months to make sure the reading isn’t a fake. He’ll also check, whether other conditions, like kidney disease, could be the source of the trouble, because hypertension is hard to be detected. The National Heart, Lung and Blood Institute recommends annual blood-pressure checks for every child over age 3.

[F] High blood pressure isn’t just an issue for adults; keeping kids blood pressure levels in a healthy range is also important. In a new study reported in Hypertension, researchers found that increased exercise duration among kids leads to lower blood pressure levels, however the same cannot be said for increased intensity.

[G] Meanwhile, make sure your kids spend more time on the playground than with their PlayStation. Even if they don’t shed a pound, vigorous exercise will help keep their blood vessels nice and wide, lowering their blood pressure. And of course, they’ll be more likely to eat light and, exercise if you set a good example.

45（）