题干

“射击运动员射击一次,命中靶心”这个事件是(  )

A:确定事件

B:必然事件

C:不可能事件

D:不确定事件

上一题 下一题 0.0难度 选择题 更新时间:2019-11-22 09:16:15

答案(点此获取答案解析)

D

同类题2

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。

    Winter is a really fun time of the year—it's great to have snowball fights and build snowmen. ____ When it's cold outside and you're not prepared, you can feel uncomfortable. Lucky for you, learning how to stay safe is not difficult.

    ____Wearing thick clothes is the best way to stay warm in the cold. Depending on where you live and how cold it is, some kids may need more clothes, some less.

    Take that hat. You maybe wear a large overcoat and ready to go, but are you forgetting something?____You'll stay much warmer with a hat than without one—tons of body heat escapes right from your head.

    Drink up. Sounds like advice for hot weather, not cold weather, right?____When you're outside in the cold and breathing hard, your body loses a lot of water through your breath. And the best way to get that water back is to drink up!

    Take it easy. Sometimes if you're out having fun, it's easy to forget to pay attention to your body. But if your body temperature drops even 4 or 5 degrees while you're outside, it can make you feel terrible.____And if you ever feel weak, those are signs that you have to take it easy indoors for a while.

A. Have a snowball fight.

B. Pull a hat onto your head.

C. Well, the truth is that it's good advice for both kinds of weather.

D. Love those clothes.

E. But you have to know how to be safe while you're out having fun.

F. You can stay outside as long as possible to fully enjoy your snow days.

G. That's why you need to be careful with your body's signals.

同类题5

 There are many colors in nature. But do you think that a color has weight? I think you'll say 6/no". But I'm afraid you are wrong. If you don't believe it, you may do a small experiment(实验).

  First, put two objects with the same weight into two boxes. Then cover the boxes.Third, wrap(包裹) one box with a red piece of paper, the other one with a white piece of paper. OK. Now hold the boxes with your hand one by one. It is certain that you will think the red one is a little heavier.

 Why do you think so? A scientist found that different colors have different weights in man's mind. That is to say, every color has its own weight in our mind.

 The scientist told us that colors also have smell. Can you smell the color? Of course not. Then why did the scientist say S07 That is because every color stands for (代表) a kind of light with a certain wavelength,(波长). It reaches our brain through sense organs

 According to this discovery, scientists say that people accept the colors they like, and refuse the colors they hate. So your body and mind will be healthy by using the colors you like. Or you'll be nervous or even get ill.  For example (例如) ,  you like blue and hate red.  If you stay in a room with red windows, wallpaper and furniture(家具) for two hours, you'll feel you have been there for four hours. But if the room is blue, you'll feel you have been there for only an hour.  And, if a person walks out of a blue room and into a red room, his temperature will rise.That means our body temperature will change with different colors.