题干

生活中我们常看到“白气”,下列有关“白气”形成的说法中正确的是(  )


A:文艺演出时舞台上经常施放“白气”,这是干冰在常温下的升华现象

B:夏天从冰箱取出的冰棍周围冒“白气”,这是空气中水蒸气的凝华现象

C:深秋淸晨的河面上经常出现“白气”,这是河面上水蒸气的汽化现象

D:冬天水烧开后壶嘴处喷出“白气”,这是壶嘴喷出水蒸气的液化现象

上一题 下一题 0.0难度 选择题 更新时间:2019-11-06 07:05:00

答案(点此获取答案解析)

D

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    When kids believe they can achieve success in math and reading, they are more likely to achieve high test scores in those subjects, new research suggests.

    Researchers used one US data set (1,354 American children) and one UK data set (13,901 British children) to measure self-concept and standardized assessments of early and later academic achievement. Self-concept is how students perceive(感知)their abilities to succeed on academic tasks. The data involved youth aged 5 to 18.

    The study considered children's earlier achievement and their characteristics and backgrounds, including birth weight, race, gender, age, and their mother's education.

    The researchers found that children's self-concept of their ability in math predicted later math achievement, while their self-concept of their ability in reading predicted later reading achievement.

    The finding suggests that the links between self-concept of ability and later achievement are specific to areas; that is, there is a link from students' self-concept about reading to reading achievement, and from students' self-concept about math to math achievement.

     “It is not unusual to see standardized measures of achievement predict achievement later in schooling, but it shows that there is more to understand.” says study coauthor Pamela Davis-Kean.

    The research also showed that success was not limited to students who perform at the top levels.

     “It involves in students with different levels of achievement in math and reading,” says Maria Ines Susperreguy, an assistant professor at Pontificia Universidad Catolica de Chile, who led the study. “Even the lowest-performing students who had a more positive view of their math and reading abilities had higher levels of achievement in math and reading.”

    Researchers say they don't know what parents or students did to create these beliefs, but it's an issue they will research further.