题干

碘盐是在食盐中添加了一定量的碘酸钾(KIO3),碘酸钾中I元素的质量分数为____(精确到0.1%),碘酸钾中碘元素的化合价为____。防辐射最有效的措施是每天摄入碘100 mg。经化验某品牌的加碘盐每1000 g中含有碘元素50 mg,若我们每天只食用加碘盐来防治核辐射,则要食用此加碘盐____g,所以每天只食用加碘盐防治核辐射____(填“合理”或“不合理”)。
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59.3%,+5,2000,不合理

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任务型阅读

    Why play sports? You might say “to get exercise” and you'd be right. To have fun? That's true, too. But there's more.____. According to the Women's Sports Foundation, girls who play sports get a lot more than just fit.

    Girls who play sports do better in school. You might think that playing sports will take up all your study time.____. Exercise improves learning, memory, and concentration (集中;专心), which can give active girls an advantage in the classroom.

    Girls who play sports learn teamwork and goalsetting skills.____. When you work with coaches, trainers, and teammates to win games and achieve goals, you're learning how to be successful. Those skills will serve you well at work and in family life.

    Sports are good for a girl's health. In addition to being fit and keeping a healthy weight, girls who play sports are also less likely to smoke. And later in life, girls who exercise are less likely to get osteoporosis(骨质疏松症).

    Playing sports improves self-confidence.____. Why? It builds confidence when you know you can practice, improve, and achieve your goals. Sports are also a feel-good activity because they help girls get in shape, keep a healthy weight, and make new friends.

    ____. Playing sports can reduce pressure and help you feel a little happier. How? The brain chemicals released during exercise improve a person's mood. Friends are another mood-lifter. And being on a team creates tight bonds between friends. It's good to know your teammates will support you both on and off the field!

A. Exercise cuts the pressure.

B. Sports teach valuable life skills.

C. In fact, there are at least 5 more reasons.

D. Regular exercise increases quality of life.

E. Girls who play sports feel better about themselves.

F. Playing sports offers children more than just physical benefits.

G. But research shows that girls who play sports do better in school than those who don't.