题干

有一种被称作“跟屁虫”的辅助装备是游泳安全的保护神。“跟屁虫”由一个气囊和腰带组成,两者之间由一根线连接。正常游泳时,连接线是松驰的,气囊漂浮着,跟人如影相随。在人体力不支等情况下,可将气囊压入水中,防止人下沉,在此情况下      (     )

A:人的重力减小了

B:气囊受到的浮力变大了

C:气囊排开水的体积变小了

D:人所受的重力方向改变了

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答案(点此获取答案解析)

B

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根据短文内容, 从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项

    Getting your children to study can be a little like getting them to eat their vegetables.

    ____ Make a study time and have it at the same time every day. This will help your kids to learn to schedule their day and will give them a sense of control over how they spend their time.

    Allow them to study in blocks of time, such as for half an hour with a five­minute break in the middle. ____ Ideal(理想的) study times are after dinner or right after school before dinner.

    Never allow your children to study in front of the television, for that will encourage passive activity. ____

    You'll also need to help your kids find the right place to study. After you've set up a good study time for little learners, set up a good place where they can get those creative juices flowing. ____ Make sure there is a table or a desk and a comfortable chair at this place.

    ____ This includes helping them out with their homework sometimes and being there for them with the answers to any questions. The input you give your children during study periods will help form a bond and help make studying enjoyable.

A. Pick a place where your children can study properly.

B. Hold them to the schedule they create for themselves.

C. Finally, spend time with your kids when they're studying.

D. Try to stop this bad habit by offering some sort of reward.

E. Keep the atmosphere light and offer lots of encouragement. too.

F. Instead, use TV as a treat or a reward when the homework is completed.

G. One of the best ways to form good study habits for your kids is to design a schedule that they keep to.