题目内容
正态分布的概率密度函数，总体标准差一愈大，曲线低而宽，随机变量在平均值μ附近出现的密度愈小；总体标准差σ愈小，曲线高而窄，随机变量在平均值μ附近出现的密度愈大。()
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The Internet can make the news more democratic, giving the public a chance to ask questions and seek【C1】______facts behind stories and candidates, according【C2】______the head of the largest US on-line services.
"But the greatest【C3】______for public participation is still in the future," Steven Case, Chairman of America On-line, told a recent meeting on Journalism and the Internet【C4】______mainly by the Freedom Forum.【C5】______, stone other experts often say the new technology of computers is【C6】______the face of journalism, giving reporters【C7】______to more information and their readers a chance to ask questions and turn to【C8】______sources.
"You don't have to buy a newspaper and be【C9】______to the four comers of that paper any more", Sam Meddis, on-line technology editor at USA Today,【C10】______about the variety of information【C11】______to computer users.
But the experts【C12】______the easy access to the Internet also【C13】______anyone can post information for others to sec. "Anyone can say anything they want,【C14】______it's right or wrong," said Case. Readers have to【C15】______for themselves whom to trust. "In a world of almost【C16】______voices respected journalists and respected brand names will【C17】______become more important, not less," Case said.
The Internet today is about【C18】______radio was 80 years ago, or television 50 years ago or cable 25 years ago, he said. But it is growing rapidly【C19】______it provides people fast access to news and a chance to【C20】______on it.
【C1】
A．Mental addiction.B．Substance independence.C．The desired effects.D．Substance dependen
听力原文： Technically, any substance other than food that alters our bodily or mental functioning is a drug. Many people mistakenly believe the term "drug" refers only to some sort of medicine or an illegal chemical taken by drug addicts. They don't realize that familiar substances such as alcohol and tobacco are also drngs. This is why the neutral term "substance" is now used by many physicians trod psychologists. The phrase "substance abuse" is often used instead of "drng abuse" to make clear that substances such as alcohol and tobacco can be just as harmfully misused as heroin and cocaine.
We live in a society, in which the medicinal. and social use of substance is pervasive: an aspirin to quiet a headache, some wine to be sociable, coffee to get going in the morning, a cigarette for the nerves. When do these socially acceptable and Obviously constructive uses of a substance become misuses？ First of all, most substances taken in excess will produce side-effects such as poisoning or intense perceptual distortions. Repeated use of a substance can also lead to physical addiction or substance dependence. Dependence is marked first by an increased tolerance, with more and more of the substance required to produce the desired eftect, and then by the appearance of unpleasant withdrawal symptoms when the substance is discontinued.
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As is known to all, the organization and management of wages and salaries are very complicated. Generally speaking, the Account Department is responsible for calculations of pay, while the Personnel Department is interested in discussions with the employees about pay.
If a firm wants to adopt a new wage and salary structure, it is essential that the firm should decide on a method of job evaluation and ways of measuring the performance of its employees. In order to be successful, that new pay structure will need agreement between Trade Unions and employers.
In job evaluation, all of the requirements of each job are defined in a detailed job description. Each of those requirements is given a value, generally in "points", which are added together to give a total value for the job. For middle and higher management, a special method is used to evaluate managers on their knowledge of the job, their responsibility, and their ability to solve problems. Because of the difficulty in measuring management work, however, job grades for managers are often decided without reference to an evaluation system based on points.
In attempting to design a pay system, the Personnel Department should compare the value of each job with those in the job market. It should also consider economic factors such as the cost of living and the labor supply.
It is necessary that payment for a job should vary with any distinctions in the way that job is performed. Where it is simple to measure the work done, as in the work done with the hands, monetary encouragement schemes are often chosen, for indirect workers, where measurement is difficult, methods of additional payments are employed.
If a company wants its new pay structure to be successful, it is necessary to______.
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