题干

一小船在静水中的速度为3m/s,它在一条河宽150m,水流速度为4m/s的河流中渡河,则该小船(   )

A:能垂直到达正对岸

B:渡河的时间可能少于50 s

C:以最短时间渡河时,它沿水流方向的位移大小为200 m

D:以最短位移渡河时,位移大小为150 m

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C

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How to get siblings (兄弟姐妹) to get along

    One of the greatest gifts of parenthood is seeing your children form a relationship with each other that is independent of you. By giving hem someone else to play with, you can free up some time for yourself. Here are four techniques you can use to help your children appreciate each other while they're young.

    ⒈____ The No.1 thing parents can do to help their kids stay on good terms with each other is not to compare them with each other. Never say “Your sister never. . ”or “Why can't you do what your brother does?”____

    ⒉Try out of the way. Try not to get too involved in your kids' arguments. Learning cooperation and problem-solving is an important skill in life____And don't blame the older one for not “knowing better,” That puts pressure on the older child and leads to unhappiness.

    ⒊Activities and opportunities. Have your kids go to their siblings' games and activities____

    “My kids go to each other's activities, and take part in activities together,” says Patricia Walters-Fischer, mother of two. Not only do her children go, but they also offer support, encouraging each other before a big game or performance and offering comfort when things don't go well.

    ⒋Vacations. Don't ignore the value of a family vacation for bringing siblings together. When kids are away from their friends and forced to spend time together, they often enjoy each other____In fact, a weekend camping trip offers some of the best opportunities for working together, having fun and experiencing something new.

A. Never shout at them.

B. Don't compare.

C. It doesn't need to be anything extremely great.

D. That only serves to fuel the competition.

E. Give them a project, and they will learn how to work together.

F. They may need help solving a conflict, but try not to take sides.

G. Get them involved in one another's lives, so they can have a better appreciation of who their sibling is.

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