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问题 选择题

下列实验能达到预期目的是（　　）

A．用稀硫酸与大理石反应制取CO2气体

B．用铜、稀硫酸和空气为原料制取硫酸铜

C．将酚酞试液滴入pH小于7的溶液中，使溶液显红色

D．二氧化碳气体中混有少量杂质氯化氢，将其通入氢氧化钠溶液中除去杂质

答案

A、实验室用稀盐酸与大理石反应制取CO2，用硫酸会因为生成硫酸钙阻碍反应的发生，故此选项错误；

B、铜的活动性排在氢的后面不会与硫酸反应生成硫酸铜，但把铜加热会生成氧化铜，氧化铜可以和硫酸反应生成硫酸铜，故此项正确；

C、能使酚酞变红色的溶液是碱性溶液，而pH小于7的溶液显酸性，故此项错误；

D、氢氧化钠溶液除去二氧化碳中混有的氯化氢气体，不能达到目的，因为这两种气体都能和氢氧化钠溶液反应，会把原物质也除去，此项错误；

故选B

单项选择题 A3/A4型题

甲公司2010年发生下列经济业务：

（1）出租固定资产取得租金收入100万元；

（2）处置无形资产产生净收益200万元；

（3）可供出售金融资产公允价值变动收益300万元；

（4）发生具有商业实质且公允价值能够可靠计量的非货币性资产交换，换出存货的账面价值低于其公允价值400万元。

甲公司直接计入所有者权益的利得为（）。

A．300万元

B．1000万元

C．600万元

D．900万元
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填空题

Of all the employed workers in the United States, 12.5 million are part of a temporary workforce. The United States Bureau of Labor Statistics counts 9.2 percent of workers as those who have______(1) they term "alternative employment arrangements." The government predicts that temporary staffing agencies______(2) experience growth of 49 percent by 2010. If numbers increase at the rate ______ (3), these companies will add 1.9 million new jobs by 2010. That’’s more than any______(4) industry.Temporary workers were the first ones to be affected by the recent economic recession, but they are______(5) to be the first to regain positions as the economy picks up and companies work to rebuild. Employers use temporary workers as a resource because_______(6) offer flexibility and come at a low cost. Many temporaries are categorized as "independent contractors" instead of employees,______(7) allows the employer to avoid______(8) certain taxes. Because they are not required to offer benefits to temporary workers, companies can save a great deal of money by hiring temps. Usually, temporary workers can qualify_______(9) benefits if they work for a staffing company for a certain length of time. Most temps, however, do not continue with one company long______(10) to qualify for them because they regard the position as a step on the ladder to a______(11) position later.According to Richard Wahlquist, president of the American Staffing Association, 75_______(12) of temporary workers hope for transition out of the temporary staffing category______(13) a period of time. Wahlquist finds that temporary workers spend about 11 weeks on various assignments before their______(14) out of the temporary workforce. Many use temporary positions to gain experience and skills______(15) they move on to better jobs. Wahlquist says that the temp workforce as a whole turns______(16) 400 percent each year.Tom Dilworth, research director at the Employment Policies Institute, explains______(17) some workers like having temporary jobs______(18) it affords them a great deal of elasticity with time and everything. Some temps only have a limited______(19) of time to work and temp agencies can help coordinate jobs to fit their schedules. Other sometimes-employees use temporary jobs to get an______(20) to a company from the inside, to get a foot in the door of a certain business or career._______(21) others take temporary positions in hopes their employers will change them over to permanent positions eventually.Nearly all the industries in the United States use temporary workers.______(22) to Tim Costello, coordinator of the North American Alliance for Fair Employment, the growth of temporary labor threatens______(23) job security of permanent workers who fear replacement, as well as the temps who are more accustomed to turnover. He predicts that there will continue to______(24) a gradual shift from permanent employees to contingent staffing, and that such a_____(25) in workplace demographics will "lead to lower wages, poorer working conditions, and more instability."
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