教学关系是静态的、固定的。

During the past 15 years, the most important component of executive pay packages, and the one .most responsible for the large increase in the level of such compensation, has been stock-option grants. The increased use of option grants was justified as a way to align executives’ interests with shareholders’. For various tax, accounting, and regulatory reasons, stock-option grants have largely comprised "at-the-money options": rights to purchase shares at an "exercise price" equal to the company’s stock price on the grant date. In such at-the-money options, the selection of the grant date for awarding options determines the options’ exercise price and thus can have a significant effect on their value.
Earlier research by financial economists on backdating practices focused on the extent to which the company’s stock price went up abnormally after the grant date, My colleagues and I focused instead on how a grant-date’s price ranked in the distribution of stock prices during the month of the grant. Studying the universe of about 19,000 at-the-money, unscheduled grants awarded to public companies’ CEOs during the decade 1996-2005, we found a clear relation between the likelihood of a day’s being selected as a grant date for awarding options, and the rank of the day’s stock price within the price distribution of the month: a day was most likely to be chosen if the stock price was at the lowest level of the month, second most likely to be chosen if the price was at the second-lowest level, and so forth. There is an especially large incidence of "lucky grants" (defined as grants awarded on days on which the stock price was at the lowest level of the month): 12 percent of all CEO option grants were lucky grants, while only 4 percent were awarded at the highest price of the month.
The passage of the Sarbanes-Oxley Act in August 2002 required firms to report grants within two days of any award. Most firms complied with this requirement, but more than 20 percent of grants continued to be reported after a long delay. Thus, the legislation could be expected to reduce but not eliminate backdating. The patterns of CEO luck are consistent with this expectation: the percentage of grants that were lucky was a high 15 percent before enactment of the law, and declined to a lower, but still abnormally high, level of 8 percent afterwards.
Altogether, we estimate that about 1,150 CEO stock-option grants owed their financially advantageous status to opportunistic timing rather than to mere luck. This practice was spread over a significant number of CEOs and firms: we estimate that about 850 CEOs ( about 10 percent) and about 720 firms ( about 12 percent) received or provided such lucky grants. In addition, we estimate that about 550 additional grants at the second-lowest or third-lowest price of the month owed their status to opportunistic timing.
The cases that have come under scrutiny thus far have led to a widespread impression that opportunistic timing has been primarily concentrated in "new economy" firms. But while the frequency of lucky grants has been somewhat higher in such firms, more than 80 percent of the opportunistically timed grants have been awarded in other sectors. Indeed, there is a significantly higher-than-normal incidence of lucky grants in each of the economy’s 12 industries.

According to the author, the Sarbanes-Oxley Act

A．effectively eliminated the practice of backdating.

B．leads to a larger percentage of lucky grants.

C．guarantees that grants are reported immediately.

D．helps to reduce the incidence of lucky grants.

变异型心绞痛（）

A.冠状动脉痉挛

B.冠状动脉内完全闭塞性血栓形成

C.心律失常诱发的心绞痛

D.1个月内新发生的心绞痛

E.心绞痛发作性质3个月内无改变

客车车厢内须按规定配置灭火器。灭火器按产品规定期限进行定期（）并涂打检查日期标记。

企业职工伤亡事故统计实行以( )为主的制度。

A．全国统一考核
B．省市考核
C．地区考核
D．城镇考核

船的力量在帆上，人的力量在心上。做民族团结工作重在交心，要将心比心，以心换心。