[Problem Solving]
试题详情
题目:
In a box of 12 pens, a total of 3 are defective. If a customer buys 2 pens selected at random from the box, what is the probability that neither pen will be defective?
选项:
A、1/6
B、2/9
C、6/11
D、9/16
E、3/4
答案:
C
| Line | Acting on the recommendation of a British |
| government committee investigating the high | |
| incidence in white lead factories of illness among | |
| employees, most of whom were women, the Home | |
| (5) | Secretary proposed in 1895 that Parliament enact |
| legislation that would prohibit women from holding | |
| most jobs in white lead factories. Although the | |
| Womens Industrial Defence Committee (WIDC), | |
| formed in 1892 in response to earlier legislative | |
| (10) | attempts to restrict womens labor, did not discount |
| the white lead trades potential health dangers, it | |
| opposed the proposal, viewing it as yet another | |
| instance of limiting womens work opportunities. | |
| Also opposing the proposal was the Society for | |
| (15) | Promoting the Employment of Women (SPEW), |
| which attempted to challenge it by investigating the | |
| causes of illness in white lead factories. SPEW | |
| contended, and WIDC concurred, that controllable | |
| conditions in such factories were responsible for | |
| (20) | the development of lead poisoning. SPEW provided |
| convincing evidence that lead poisoning could be | |
| avoided if workers were careful and clean and if | |
| already extant workplace safety regulations were | |
| stringently enforced. However, the Womens Trade | |
| (25) | Union League (WTUL), which had ceased in the late |
| 1880s to oppose restrictions on womens labor, | |
| supported the eventually enacted proposal, in part | |
| because safety regulations were generally not being | |
| enforced in white lead factories, where there were | |
| (30) | no unions (and little prospect of any) to pressure |
| employers to comply with safety regulations. |
| Line | Frazier and Mosteller assert that medical research |
| could be improved by a move toward larger, simpler | |
| clinical trials of medical treatments. Currently, | |
| researchers collect far more background information | |
| (5) | on patients than is strictly required for their trials— |
| substantially more than hospitals collect—thereby | |
| escalating costs of data collection, storage, and | |
| analysis. Although limiting information collection | |
| could increase the risk that researchers will overlook | |
| (10) | facts relevant to a study, Frazier and Mosteller |
| contend that such risk, never entirely eliminable from | |
| research, would still be small in most studies. Only | |
| in research on entirely new treatments are new and | |
| unexpected variables likely to arise. | |
| (15) | Frazier and Mosteller propose not only that |
| researchers limit data collection on individual | |
| patients but also that researchers enroll more | |
| patients in clinical trials, thereby obtaining a more | |
| representative sample of the total population with | |
| (20) | the disease under study. Often researchers restrict |
| study participation to patients who have no ailments | |
| besides those being studied. A treatment judged | |
| successful under these ideal conditions can then be | |
| evaluated under normal conditions. Broadening the | |
| (25) | range of trial participants, Frazier and Mosteller |
| suggest, would enable researchers to evaluate a | |
| treatments efficacy for diverse patients under various | |
| conditions and to evaluate its effectiveness for | |
| different patient subgroups. For example, the value | |
| (30) | of a treatment for a progressive disease may vary |
| according to a patients stage of disease. Patients | |
| ages may also affect a treatments efficacy. |
| Line | In a 1918 editorial, W. E. B. Du Bois advised African |
| Americans to stop agitating for equality and to | |
| proclaim their solidarity with White Americans for | |
| the duration of the First World War. The editorial | |
| (5) | surprised many African Americans who viewed |
| Du Bois as an uncompromising African American | |
| leader and a chief opponent of the accommodationist | |
| tactics urged by Booker T. Washington. In fact, | |
| however, Du Bois often shifted positions along the | |
| (10) | continuum between Washington and |
| confrontationists such as William Trotter. In 1895, | |
| when Washington called on African Americans to | |
| concentrate on improving their communities instead | |
| of opposing discrimination and agitating for political | |
| (15) | rights, Du Bois praised Washington’s speech. In |
| 1903, however, Du Bois aligned himself with Trotter, | |
| Washington’s militant opponent, less for ideological | |
| reasons than because Trotter had described to him | |
| Washington’s efforts to silence those in the African | |
| (20) | American press who opposed Washington’s |
| positions. | |
| Du Bois’s wartime position thus reflected not a | |
| change in his long-term goals but rather a | |
| pragmatic response in the face of social pressures: | |
| (25) | government officials had threatened African |
| American journalists with censorship if they | |
| continued to voice grievances. Furthermore, | |
| Du Bois believed that African Americans’ | |
| contributions to past war efforts had brought them | |
| (30) | some legal and political advances. Du Bois’s |
| accommodationism did not last, however. Upon | |
| learning of systematic discrimination experienced | |
| by African Americans in the military, he called on | |
| them to “return fighting” from the war. |
According to the passage, which of the following is true of the strategy that Du Bois’s 1918 editorial urged African Americans to adopt during the First World War?
A recent court decision has qualified a 1998 ruling that workers cannot be laid off if they have been given reason to believe that their jobs will be safe, provided that their performance remains satisfactory.