题干

某实验室的废液中,可能含有FeCl3、NaCl、Na2SO4、Ba(NO3)2中的一种或多种。某同学取该废液样品观察为无色溶液,向其中滴加BaCl2溶液产生白色沉淀,继续加稀硝酸无明显现象。根据以上实验现象分析,下列推断正确的是

A:可能存在NaCl

B:可能存在Na2SO4

C:一定存在FeCl3

D:一定存在Ba(NO3)2

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A

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    “Educational researchers, political scientists and economists are increasingly interested in the characteristics and skills that parents, teachers and schools should foster in children to increase chances of success later in life,” said lead author Marion Spengler, PhD of the University of Tubingen.” Our research found that specific behaviors in high school have long-lasting effects for one's later life.”

    Spengler and her co-authors analyzed data collected by the American Institutes for Research from 346, 660 U. S. high school students in 1960, along with follow-up data from 81,912 of those students 11 years later and 1,952 of them 50 years later. The initial high school phase measured a variety of student behaviors and attitudes as well as personality characteristics, cognitive abilities, parental socioeconomic status and demographic(人口统计的)factors. The follow-up surveys measured overall educational attainment, income and occupational prestige(声望).

    Being a responsible student, showing an interest in school and having fewer problems with reading and writing were all significantly associated with greater educational attainment and finding a more prestigious job both 11 years and 50 years after high school. These factors were also all associated with higher income at the 50-year mark. Most effects remained even when researchers controlled parental socioeconomic status, cognitive aibility and other broad personality characteristics such as conscientiousness.

    While the findings weren't necessarily surprising, Spengler noted how reliably specific behaviors people showed in school were able to predict later success.

    Further analysis of the data suggested that much of the effect could be explained by overall educational achievements, according to Spengler.

    “Student characteristics and behaviors were rewarded in high school and led to higher educational attainment, which in turn was related to greater occupational prestige and income later in life,” she said. “This study highlights the possibility that certain behaviors at crucial periods could have long-term consequences for a person's life.”