24，生产成本对资本主义现实生产的影响A．它只是资本家账簿上的项目，它对现实的资本主

阀型避雷器安装地点出现对地电压大于其最大允许电压时，避雷器会爆炸，在中性点不接地系统中最大允许电压取1．1倍线电压，中性点接地系统取0．8倍线电压。

由学习引起的行为或行为潜能的变化是能够相对持久的。（　）

阅读理解

     Cut out part of a healthy person's liver and transplant it into a sick person--it sounds like a

complicated and dangerous operation , not to mention very expensive. But it is sometimes the

only possible cure for a seriously ill patient with liver disease.

     Until now British scientists have just announced a new stem cell technique, which allows them

to grow healthy liver cells outside human bodies. According to the researchers, it could be another

five to 10 years before the technique can actually be used to help patients with liver disease.

However, they say the method might one day replace liver transplants altogether. The study was

led by the University of Cambridge and the Welcome Trust Sanger Institute, a British genomics

and genetics research institute. It was published in the journal nature on October 12,2011.

     The researchers took skin cells from a patient with a mutation (变异) in a gene called

alphal-antitrypsin (a-l抗胰蛋白酶). This gene makes a protein that protects our bodies against

inflammation (炎症). People with changed or damaged alphal-antitrypsin are not able to release

the protein correctly from the liver, so the protein is trapped there and eventually leads to liver

cirrhosis (肝硬化).

     Scientists then used an advanced technique to cut away the faulty section of DNA from a stem

cell and replace it with a corrected one, according to the journal. The stem cells went on to produce

fresh and healthy liver cells with normal protein levels. Scientists put the new liver cells into mice

and found that they worked very well.

     Stem cells are the life source of all other cells in the body. They could transform medicine,

providing treatment for blindness, spinal cord injuries and other serous injuries. They could also be

used to produce new cells for damaged organs.

     David Lomas, a Cambridge biology professor who worked on the team, said: "If we can use a

patient's own skins cells to produce liver cells that we can put back into the patient, we may prevent

the future need for transplantation. "

1. what is the best title of this passage?

A. How to transplant liver for patients

B. A new way to transplant livers for patients  

C. The difficulty in curing liver patients

D. New life for liver patients

2. The first paragraph is written to _______.

A. show how difficult it is to cure liver disease  

B. tell us what a liver transplant involves    

C. introduce a potential cure for liver disease

D. show how serious liver disease can be

3.Why do some people get liver cirrhosis according to the article?

A. Because their bodies are lacking in alphal-antitrypsin.

B. Because their skin cells are not able to protect against inflammation.

C. Because the alphal-antitrypsin in their bodies is changed or damaged.

D. Because their liver releases too high a level of protein.

4. According to British scientists, liver transplant might ___________.

A. become history sooner or later

B. be replaced by a new stem cell technique in five years

C. be the only possible cure liver disease in the future

D. be prevented in the future

5. What can be inferred from the passage?

A. Stem cells can keep liver cells healthy and fresh.    

B. Equaling medicine, stem cells can cure blindness, spinal cord injuries and other serous injuries

C. Stem cells can replace the damaged organs.

D. All other cells in the body can't work well without stem cells

下列关于信用卡最低还款额的描述，错误的是( )。

Ⅰ．信用卡持卡人按照信用卡最低还款额还款是一种值得推荐的理财方式，可以无限期地推迟还款期限

Ⅱ．最低还款额仅包括信用额度内消费款的10% ，不包括银行费用和利息

Ⅲ．最低还款额仅包括银行费用和利息，不包括消费款的本金

Ⅳ．使用最低还款额的方式还款，随着可还清时间的推移，相应地所负担的利息总额也越高

A．Ⅰ、Ⅲ
B．Ⅱ、Ⅲ
C．Ⅰ、Ⅱ、Ⅲ
D．Ⅰ、Ⅱ、Ⅲ、Ⅳ

School authorities often refuse to face the problem of drug-abuse; government drug-abuse agencies have done too little to inform the public about it; many physicians still seem unaware of it when they examine teenagers. As a result, parents may still be the last to know that their children have fallen victim to the drug epidemic that has been raging for more than a decade among American’s youth. In a survey of a middle-income Cincinnati suburb, 38 percent of the sixth grade and 89 percent of the senior class said they used drug and alcohol; 48 percent of the parents thought their children used alcohol, but only 8 percent thought their children used drug.

Fortunately, there is a new force at work against this epidemic—a nationwide movement of more than 400 parent groups formed to expose and battle drug use among teenagers and preteens. The groups have different approaches and widely varying rates of success. Yet this parental crusade is the only major force in the country to have taken active, organized and effective steps aimed at stopping marijuana use.

Why the concentration on marijuana Marijuana is the illegal drug most used by kids. According to a National High School Survey, 44 percent of U. S. high school seniors had smoked pot during their school years, and one out of seven of these were daily or near daily smokers. There was a close-related connection between pot smoking and subsequent use of cocaine and heroin by young men. Of those who had smoked pot fewer than 100 times, seven percent had graduated to cocaine, four percent to heroin. But of those who had smoked pot at least 1,000 times, 73 percent had gone on to cocaine, and one out of three had graduated to heroin.

Parent groups have found that by stopping their kids from smoking pot, they almost automatically stop all other illegal drugs, and cut down on alcohol use as well. The High School Senior Survey’s statistics show that heavy pot smokers tend to be heavy drinkers, while those who do not use pot tend not to drink heavily.

Since virtually all over the country teenage " partying " has come to mean " getting smashed and getting stoned " on anything from pot to pills to hashish, LSD, and alcohol, some parent groups home in on the partying aspect. Parents Who Care (PWC) was started in 1979 by 15 Palo Alto, Calif., parents who were upset by stories of serious drug problems at parties. They held talk sessions with their children and learned that most of their children had never been to a party where the main activity was not getting high. The parents’ solution: workshops showing kids how to give successful drug-and-alcohol-free parties. Says Margery Ranch, PWC director, " We’ve seen a change in attitude. Young people are feeling more comfortable saying no.

According to the passage, which of the following is TRUE（）

A. Cutting down alcohol use may help stop drug-abuse

B. Among the illegal drugs, cocaine is very popular among kids

C. Heavy pot smokers are heavy drinkers

D. Giving up pot smoking may contribute to abandoning other illegal drugs