题干

在平坦的垒球运动场上,击球手挥动球棒将垒球水平击出,垒球飞行一段时间后落地.若不计空气阻力,则(    )

A:垒球落地时瞬时速度的大小仅由初速度决定

B:垒球落地时瞬时速度的方向仅由击球点离地面的高度决定

C:垒球在空中运动的水平位移仅由初速度决定

D:垒球在空中运动的时间仅由击球点离地面的高度决定

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D

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How can I fight laziness?

    Lazy people will never amount to anything in life. However, laziness can be defeated once a few changes have been made in your mind.

    ____Many people lack sleep constantly, since they stay up too late and get up too early to prepare for work. These people have little motivation once they arrive home. Laziness works hand in hand with a lack of motivation and a tendency to put off things. By adjusting your sleep schedule to provide a few more hours of meaningful rest, you can fight laziness throughout the day.

    Another way to fight laziness is to change your mind from passive to active. Some people treat their lives as if they were pushed from task to task. Others take a more proactive approach, viewing each task as a challenge they must overcome alone.____

    Some people fight laziness by removing the temptations that surround them. A television in the living room may provide entertainment, but watching too much TV often contributes to laziness. Create a reward system for yourself, just as parents do for a child to promote responsibility.____

    ____Spouses and children may all have different energy levels, but laziness can be spread if not dealt with immediately. To fight household laziness, lead by example. Be the first to collect and wash dishes after a meal. Others in the home may eventually follow your example and perform their own task. It is difficult to practice laziness when your are surrounded by motivated people.

    ____Enough exercise and a balanced diet can help you to develop a healthy lifestyle, thus enabling you to have more energy and help lift your spirits.

A. Knowing how to fight laziness is important.

B. One way to fight laziness is to get enough sleep.

C. Laziness can also be a lasting problem at home.

D. Complete a few tasks and reward yourself with what you enjoy, such as a good dinner or a film.

E. Finally, taking exercise regularly can help you fight laziness.

F. With strong determination, you will be able to achieve your goal.

G. Laziness sets in when you no longer feel in charge of your own life.