单项选择题

Questions 10—11 are based on the following:
Antinuclear activist: The closing of the nuclear power plant is a victory for the antinuclear cause. It also represents a belated acknowledgment by the power industry that they cannot operate such plants safely.
Nuclear power plant manager: It represents no such thing. The availability of cheap power from nonnuclear sources, together with the cost of mandated safety inspections and safety repairs, made continued operation uneconomic. Thus it was not safety considerations but economic considerations that dictated the plant’s closing. Do strong electric currents, by means of the electromagnetic fields that accompany them, cause cancer in people who live and work nearby Telephone line workers, who work near such currents every day, can provide a test case. They show elevated levels of brain cancer; therefore, the hypothesis of electromagnetic causation is supported. Which of the following, if true, most seriously weakens the argument

A. Burying power lines and other measures to protect the public from such electromagnetic fields would be prohibitively expensive.
B. Telephone line workers are exposed to levels of chemical solvents high enough to cause brain cancer.
C. High exposure to strong electromagnetic fields is correlated with a slightly higher-than-normal incidence of childhood leukemia, which is a form of cancer.
D. Public health officials who found that a group of different illnesses in people living near a power substation could not reliably be attributed to its electromagnetic field were accused of covering up the facts.
E. Telephone line workers, like most people have electrical appliances at home, and most electrical appliances, when turned on, are surrounded by an electromagnetic field of some measurable level.

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单项选择题Headhunters are firms that, for a fee, undertake to recruit for their clients personnel who are greatly needed yet hard to find. The clients, in turn, require that they be offlimits to headhunters whose services they buy; i.e., headhunters cannot raid one client’s staff on behalf of other clients. Of the following, which would, if feasible, be the best strategy for a company to pursue if that company wanted both to use headhunters to fill a vacancy and, if successful in filling the vacancy, to reduce the risk of losing the newly hired employee to a competitor

A. Find out which headhunters recruit workers of the sort being sought and employ all those headhunters.
B. Find out which headhunter has the highest success rate in recruiting for its clients and hire that firm.
C. Find out how much the company’s competitors currently pay staff of the sort being sought and offer to pay prospective employees higher salaries.
D. Find out whether any of the company’s competitors are seeking to recruit workers of the sort being sought and, if so, make sure not to hire the same headhunters that they hire.
E. Find out which of the company’s competitors are on the client lists of the headhunters who are being considered for the job.

单项选择题On a certain day it took Bill three times as long to drive from home to work as it took Sue to drive from home to work. How many Kilometers did Bill drive from home to work (1)Sue drove 10 kilometers from home to work, and the ratio of was the same for Bill and Sue that day. (2)The ratio of for Sue that day was 64 kilometers per hour.

A. 条件(1)充分，但条件(2)不充分．
B. 条件(2)充分，但条件(1)不充分．
C. 条件(1)和(2)单独都不充分，但条件(1)和条件(2)联合起来充分．
D. 条件(1)充分，条件(2)也充分．
E. 条件(1)和条件(2)单独都不充分，条件(1)和条件(2)联合起来也不充分．