已知R2O5的相对分子质量为142，则R的相对原子质量为（ ） A．31 B．6

牙片可检查（）

A.龋损情况

B.牙齿色泽

C.髓角位置

D.牙槽骨情况

E.根管长短

（）是两人遵照一定的规则，使用掤、捋、挤、按、采、挒、肘、靠等手法，双方粘连黏随，通过肌肉的感觉来判断对方的用劲，然后借劲发劲将对手推出或推倒，以此决定胜负的竞技项目。

离心泵汽蚀余量Δh随流量Q的增大，汽蚀余量Δh（）。

A、增大

B、减小

C、不变

D、先增大，后减小

An analysis of workplace trends shows that employee perks, a reliable indicator of job market strength, are beginning to make a comeback. While not as Extravagant as those offered in the late 1990s, companies clearly are shifting their focus from workforce reduction to workforce retention. Firms realize that they require a foundation of experienced, trained, and motivated workers. These employers are improving and/ or adding perks to prevent an exodus of workers that could occur as the economy continues improving. They also may be looking further down the road when severe labor shortages are expected to return.

An analysis of perks offered in today’s workplace shows that many of the 1990s-style benefits, such as game rooms and luxury car leases, have been abandoned. The perks that remain popular with employers and employees are those that help workers stay healthy, career focused, and financially stable. Perhaps the most appreciated are those that help individuals maintain work-life balance.

Work-life balance is just one part of the growing concern companies have about the overall emotional and physical health of their workers. Employees who are stressed out or depressed because they do not feel as if they are giving enough attention to the nonwork aspects of their lives ultimately are unproductive. More and more companies also are learning that workers desire the opportunity to grow professionally in the workplace. HewlettPackard, for instance, has boosted its employee education and development budget by 20%.

Nationwide Insurance, based in Columbus, Ohio, established a career-planning website in 2003. The site provides information on company job opportunities, career development, and an in-house mentoring program. Nationwide also is helping to educate its employees in financial matters, acknowledging that workers distracted by such issues on the job are not giving their full attention to the company’s priorities. It is adding classes and seminars on personal finance issues and 401(k) investments.

Sometimes perks simply are about keeping employee morale elevated. Knowing that an improving economy might prompt valued employees to seek new opportunities, the owner of Ticketcity. com has lavished his best performers with tickets to the Masters golf tournament (锦标赛), access to country clubs, and invitations to a management retreat in Sedona, Ariz.

Moreover, even companies that cannot afford to institute costly perks can find ways to make sure current employees are happy. Doug Dorman, vice president of human resources for the Greenville (S.C.) Hospital System explains that there is a definite sense of urgency when it comes to employee retention, knowing that labor shortages are returning. Dorman notes, however, that they have not focused on perks, "but rather on creating a culture of recognition and appreciation. Employees stay when they have good two-way communication with management and are truly appreciated and recognized for their contributions.

The underlined word "perks" (Line 1, Paragraph 1) most probably means （）

A. a payment or profit received in addition to a regular wage or salary

A. release of entertainment facilities such as game rooms or luxury cars

C. the balance between the work and balance of employees

D. the opportunities to improve one’ s expertise in his work

从所给的四个选项中，选择最合适的一个填入问号处，使之呈现一定的规律性：（）

A.A

B.B

C.C

D.D