历代政府都注重加强法制建设。法律对人类社会的积极作用不包括（） A．稳定社会秩序

钢门窗工程量应按( )计算。

A．樘

B．门窗洞口面积

C．门窗框外围面积

D．门窗扇面积

在空中某一位置，以大小v₀的速度水平抛出一质量为m的物体，经时间t物体下落一段距离后，其速度大小仍为v₀，但方向与初速度相反，如图所示，则下列说法中错误的是(不考虑空气阻力) （   ）

A．风力对物体做功为零

B．风力对物体做负功

C．物体机械能减少mg²t²／2

D．物体的速度变化为2v₀

阅读理解。

     Between school, homework, sports, your afterschool job, and hanging out with friends, it may feel

like there's no time for healthy eating. And when you do stop to eat, it's probably tempting to go the

quick and easy route by grabbing a burger and fries, potato chips, or candy.

     Even if you take time to eat three meals a day, you may still feel hungry at times.  This is natural-during

teens, a person's body demands more nutrients to grow. What's the answer? Healthy snacks. Snacking

on nutritious food can keep your energy level high and your mind alert without taking up a lot of your

time. Snacks are a great way to satisfy that hunger and get all the vitamins and nutrients your body

needs.

     But you need to pay attention to what you eat. Filling your face with a large order of fries after class

may give you a temporary help, but a snack high in fat and calories will only slow you down in the long

run.

     To keep energy levels going-and avoid weight gain-keep clear of foods with lots of simple

carbohydrates (sugars) like candy bars or soda. Look for foods that contain complex carbohydrates

like wholegrain breads and cereals and combine them with proteinrich snacks such as peanut butter or

lowfat yogurt (酸奶) or cheese.

     Choosing healthy snacks means shopping smart. Be careful of the health claims on food packages.

Just because something is "all natural" or "pure" doesn't necessarily mean that it's nutritious. For example, "all natural" juice drinks or sodas can be filled with sugar (which is, after all, a natural ingredient) but all

that sugar means they'll be high in calories and give you little nutrition.

     A granola (麦片) bar is a good example of a snack that people think is healthy. Although granola

bars can be a good source of certain vitamins and nutrients, many also contain a great deal of fat,

including a particularly harmful type of fat called trans fat (反式脂肪酸). Check the Nutrition Facts label

on the package to be sure.

1. People think that granola bar is healthy because ________.

A. it is a good source of calories                        

B. it provides trans fat

C. it contains some vitamins          

D. it is natural

2. In choosing healthy snacks, we should try to make sure that ________.

A. they are all natural or pure                          

B. they are high in nutrition

C. their packages are good                  

D. they contain harmless fat

3. Teens need snacks to ________.

A. keep a good figure            

B. gain weight

C. help grow                  

D. keep healthy

4. According to the passage, all the following snacks are good EXCEPT ________.

A peanut butter                        

B. fries

C. lowfat yogurt                        

D. wholegrain bread

电压互感器二次短路后会产生什么后果？

表示要找出满足A和B的全部文献

A．A＊B
B．A+B
C．A－B
D．GT
E．GE