题干

物体做平抛运动,正确的说法是:

A:由于物体只受重力,所以物体在下落过程中只受重力的冲量

B:尽管物体只受重力,物体在曲线下落过程中动量变化量的方向也不会竖直向下

C:轻物体和重物体在自由下落中,只要经过的时间相同,重力的冲量也相同

D:物体在下落过程中,相等时间内的平均速度不相同,所以相等时间内重力的冲量也不相同

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A

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    We all wish we had just a bit more time. Just think what you could do with an extra hour or two each day: you could finally stick to an exercise routine, or spring-clean the house, or write your novel, or learn the guitar and so on. ____ But I can help you find more hours in your day for the things that really matter.

1). Get Out of Bed Earlier

If you normally get up at 7: 30 a. m. , try getting up at 7: 00 a. m. That half-hour might not sound like much, but it could be time that you use to exercise, to read that book you've been meaning to finish. ____

2). Do the Important Tasks First

    Once you get to work, get the important ones done first (not the easy ones, or even the urgent ones). You can afford to spend at least an hour working on big, important tasks rather than on all those little urgent ones. ____The urgent tasks will still get done, and you won't miss the important ones.

3). Reduce Interruptions

    If colleagues have a habit of hanging around your desk to chat, or if the phone is constantly ringing, you might find that it takes you half the day to finish a simple task like writing a letter. Constant interruptions don't just eat up time, they also break your concentration.

    When you've got a big task to focus on, let your calls go to voicemail. ____Wearing headphones makes it less likely that people will try to strike up a conversation.

4). ____

    A few minutes chatting, browsing the web, and so on, can easily turn into hours of wasted time over the course of a day. When you're working, work. If your concentration is slipping, take a proper break: go and get a glass of water, or stretch your legs a bit. And if you're facing a difficult task, try breaking it into small steps or stages so that it's easier to deal with.

A. Or simply to get your day off to a calm and organized start.

B. I can't magically make all your days 25 hours long.

C. Would you want me to make your day longer?

D. Take Breaks When Necessary

E. If you have an office door, close it.

F. If you work like this, you'll usually save time.

G. Stay Focused on Your Work