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问题 填空题

课外小组的同学为了验证物质是由微观粒子构成的以及它们的性质，用家里的蔗糖做了如下实验：

（1）甲同学将蔗糖细细研磨；乙同学将蔗糖溶于水，蔗糖不见了，得到的糖水变甜了．能证明蔗糖是由微观粒子构成的同学是 _________ （填“甲”或“乙”）．

（2）乙同学在得到的糖水中又加了一些水，充分搅拌，糖水的甜度降低了，用知识解释甜度降低的原因是                                         ．

答案

（1）乙

（2）单位体积糖分子变少了

单项选择题

Modern industrial society grants little status to old people. In fact, such a society has a system of built-in obsolescence. There is no formal system for continuing our education throughout our life in order to keep up with rapidly changing knowledge. When our education and job skills have grown obsolete, we are treated exactly like those who have never gained an education or job skills and are not encouraged or given the opportunity to begin anew.As a society becomes more highly developed, the overall status of older people diminishes. Improved health technology creates a large pool of old people, who compete for jobs with the young. However, economic technology lowers the demand for workers and creates new jobs for which the skills of the aged are obsolete, forcing older people into retirement. At the same time, young people are being educated in the new technology and are keeping pace with rapid changes in knowledge. Finally, urbanization creates age-segregated neighborhoods. Because the old live on fixed incomes, they must often live in inferior housing. All these factors — retirement, obsolete knowledge and skills, inferior standards of living — lower the status of the aged in society.A century ago, when one could expect to live only to 50 or so, the life span more or less coincided with the occupation and family cycle. But today the average life span allows for fifteen to twenty years of life after these cycles. It appears that our life span is outpacing our usefulness in society.

The sentence "our life span outpaces our usefulness" means we can live longer________.

A．and make progress

B．and do more work

C．but move slowly

D．but become useless
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单项选择题

下列对楼层工作间布草管理的描述，不正确的是哪项（）？

A.将楼层棉织品配置清单张贴在楼层工作间内

B.每个楼层工作间内应放置记录本，对客人借用或加床所用的棉织品情况做好记录

C.每季度都需要用消毒抹布擦拭墙面，拖擦地面，对工作间进行消毒

D.布草架顶上不得摆放与工作无关的物品
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