如图所示,三维坐标系的轴方向竖直向上,所在空间存在沿轴正方向的匀强电场。一质量为

题型:选择题

问题:

如图所示,三维坐标系轴方向竖直向上,所在空间存在沿轴正方向的匀强电场。一质量为、电荷量为的小球从轴上的点以速度水平抛出,点坐标为(),重力加速度为,场强。则下列说法中正确的是(  )

A.小球运动的轨迹为抛物线

B.小球在平面内的分运动为平抛运动

C.小球到达平面时的速度大小为

D.小球的运动轨迹与平面交点的坐标为(

考点:牛顿第二定律
题型:选择题

阅读下面短文,按要求完成各项任务。.

Breaking Bad Eating -Habits

Have you heard the expression "You are what you eat"? Well, do you like who you are’’ If not, break some bad eating habits and feel better about yourself.

Bad habit 1: ______________

Many packaged ( =" in" small bags) foods, such as frozen (纤维) dumplings ,rice rolls and instant noodles (方便面) have lots of fat and calories (热量).

The solution: Read the instructions to find the healthiest foods that are low in salt and nigh in fiber Also check to make sure they have ingredients such as vegetables and grains When possible, use packaged foods as part of a "home-cooked" meal. For example frozen (纤维) dumplings with fresh vegetables are better than dumplings alone.

Bad habit 2:_____________________________________________

People without breakfast don’t have enough energy they need to get through the morning. Eating breakfast improves your concentration, memory (冰冻的) and mood.

The solution: Always keep a kind of quick foods like yogurt. Or have a standing order a! breakfast place.

Bad habit 3:_________________________________________________

It takes your body at least 20 minutes to "tell" your brain that you are full, So last eaters usually eat more than people who eat slowly.

The solution: Try to slow down. Try eating at least some of your meals without I V, hand phones or computers. Use a plate or bowl when you eat.

Bad habit 4:______________________ ______________

Healthy snacks between meals are fine. But when you snack instead of having real meals, you will not eat your meals regularly. Plus, snack foods such as chips and sweets aren’t very satisfying That makes it easy to overeat.

The solution: To get more energy, allow yourself two healthy snacks a day. Choose snacks that will make you feel full. Try fruit, yogurt or nuts.

As we all know, bad habits can be broken. Take the first step toward a healthier eating routine(常规)——star following these tips today!

小题1:给文中的横线处选择合适的标题,并将其字母代号填写在下面的横线上.(2分)

a. You are a fast eater.

b. You often don’t eat breakfast.

c. All your meals come in packages.

d. You snack too much.

Bad habit 1:_____   Bad habit 2:_____   Bad habit 3:_____  Bad habit 4:_______

Bad habit 1:_c_ Bad habit 2:_b Bad habit 3:_a___Bad habit 4:d_______

小题2:列举出文中提到的三种packaged foods: (1 分)

_______________  ____________________  ___________________

小题3:根据上下文,将文中划线句子译成汉语(2分)

It takes your baby at least 20 minutes to “tell” your brain that you are full.

                                                              

小题4:根据文章内容完成句子。(2分)

No eating breakfast is bad influence on your_________________, __________________,______________________ and __________________________

小题5:回答问题;How can you eat snacks healthily? (至少答出两种方式) (2分)

______________________________________________________________________________________________________________________________________________________________

小题6:从文中找出与所给句子意思相同或相近的句子。(1分)

Your heaith depends on the food you eat.

_______________________________________________________________________________

题型:选择题

日常生活中下列做法属于化学变化的是(    )

A.给自行车打气

B.苹果腐烂

C.蔗糖溶解

D.用砂纸去铁皮表面的铁锈

题型:选择题

急性白血病易继发感染的直接原因是()。

A.白血病细胞大量增殖

B.白血病细胞全身浸润

C.多发性出血而吸收

D.白血病细胞抑制正常粒细胞产生

E.白血病细胞大量死亡分解

题型:选择题

科研成果是衡量科学研究任务完成与否、质量优劣以及科研人员贡献大小的重要标志。

题型:选择题

=()。

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