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已知连锁遗传杂合体Abc/aBC中，a、b之间的交换值为20%，b、c基因之间的交换值为10%，在无干扰情况下，杂合体自交产生8种类型的配子。问：

【参考答案】

杂合体Abc/aBC由于a、b之间单交换产生ABC和abc2种配子。$杂合体Abc/aBC由于3对基因的双交换产生ABc......

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Text 2Empowering workers constitutes the first step toward a stronger economy and stronger citizen-ry. It is a vital step toward overcoming inequality in American society. During the 1980s, the need for better wages for all workers increased as women, traditionally secondary earners, assumed grea- ter responsibility for their own and their children's well-being. Yet the ability to raise families to a decent living standard through wage work decreased; real wages fell for most workers. And the Federal Govemment enacted no new policies to facilitate the integration of work and family, as working women and working families suffered a loss in political power as well.Black or Hispanic women are four times as likely to be low-wage workers as are white men with comparable skills and experiencE.White women are more than three times as likely as white men to be low-wage workers, and black or Hispanic men more than one-and-a-half times as likely. More than half of all low-wage workers are the only wage workers in their families, or live alonE.Employment no longer provides an escape from poverty. More than eight million working adults are poor; two million of them work full-time, year-rounD.More than seven million poor children have at least one working parent. When that one working parent is a low-wage worker, thechildren have no better chance of escaping from poverty than if the parent were not working at all ;more than two-fifths of such children are poor.Even if generous income assistance were available, the wages employers pay would be held toa minimum. In addition, policies such as tax credits for working parents do nothing to increase the olitical power of working women and men.Our research shows that unionization is among the most effective strategies for raising pay, especially for women and minority men. Being a union member, or being covered by a collective-bargaining agreement, raised 1984 wages by $ 1. 79 per hour for Hispanic men, $ 1. 32 for black en, $ 1.26 for Hispanic women, $ 1. 01 for black women, $ 0. 68 for white women, and $ 0.41 for white men, when all other factors, such as occupation, industry, firm size, education and experience were held constant. In percentage terms, the union increase was more than 15 per- cent for blacks and Hispanics, 11 percent for white women, and 4 percent for white men.46. During the l980s, women started to play a more important role in[ A] demanding political rights.[ B ] improving social welfarE.[ C] supporting the family.[ D] earning better wages.
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