题干

甲、乙两种固体物质的溶解度曲线如下图所示。下列说法正确的是(       )

A:20 ℃时,甲溶液中溶质的质量分数一定比乙溶液的大

B:将40 ℃时甲的一定量饱和溶液降温至20 ℃,溶液质量不变

C:甲的溶解度大于乙的溶解度

D:40 ℃时,分别在100 g水中各加入30 g甲、乙,同时降温至20 ℃,甲、乙溶液均为饱和溶液

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D

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    White-collar workers increasingly unhealthy

    An increasing number of white-collar workers in Shanghai are getting failing grades on their physical examinations, according to a white paper on the health of white-collar workers in Shanghai.

    Carried out by Shanghai Foreign Service Group,a human resources company,the report indicated that more than 53 percent of males are overweight,46 percent suffer from a fatty live and about 26 percent have elevated blood lipids(血脂).However,females are more often diagnosed as having breast lesions(乳房病变)that could lead to cancer (85 percent),thyroid(甲状腺)disorder (34 percent) and hemorrhoids(痔疮)(23 percent).

    Though the report also found that white-collar workers were paying increasing attention to their health—with about 84 percent saying they followed their condition closely or very closely—those with healthy lifestyles dropped to 64 percent last year from 77 percent in 2015.

    The report came from about 500,000 physical exams taken by while-collar workers in Shanghai over the past five years.“I always eat and drink too much and never exercise,”said Wei Ruoxi,a 26-year-old working in finance who is struggling with being overweight.“I know what a healthy lifestyle looks like,but the job just brings too much pressure and squeezes out exercise time,”she added.Hu Xiaolong,30,an accountant in Shanghai,said he was determined to live healthily from now on.“My recent physical examination shows a little shadow in the lung,which startled me when I heard it.I really need to quit these habits like smoking and staying up late.”

    The white paper also showed that more people are turning to commercial health insurance to cope with financial risks caused by health problems.The popularity of insurance purchases among the participants reached 15.3 percent last year,a rise of 4 percentage points in just one year.Most participants also expected their companies to help them with effective health management,such as offering membership cards for gyms,flexible working schedules and regular physical examinations.