将学习失败归因于自己的能力不足会提高学习的积极性。( )

阅读短文，选择正确答案。

    Are you carrying too much on your back to school? I'm sure lots of your age will say "Yes". Not only the

students in China have this problem, but children in the United States also have heavy school bags.

    Doctors are starting to worry about that younger and younger students are having problems as a result of

school bags being too heavy for them. 

    "It's hard for me to go upstairs with my bag because it's so heavy," said Rich Hammond, an 11-year-old

student in the US.

    Rich is among students who have common school bags with two straps to carry them, but many other

choose rolling (转动的) bags.

    But even with rolling bags, getting up stairs and houses is still a problem for children. Many of them have

hurt backs and necks because of the heavy school bags.

    But how much is too much? Doctors say students should carry no more than 10% to 15% of their own

body weight.

    Scott Bautch, a black doctor, said children under Grade 4 should stay with 10%. But it is also important that

older children don't stay with over 15%, because their bodies are still growing. "Children are losing their balance

and falling down with their school bags," he said.

    Parents and teachers are starting to tell children to only take home library books that they will be reading at

night. Some teachers are using pieces of paper or thin workbooks for students to take home.

    One of the best answer is , as some children said ,to have no homework at all.

1. From the passage we can learn that ______. [ ]

A. only children in China carry too heavy school bags

B. children in other countries don't carry too heavy school bags

C. both children in China and the US carry too heavy school bags

D. only children in the US carry too heavy school bags

2. Children feel it hard for them to go upstairs because ______. [ ]

A. they are too young

B. their school bags are too heavy

C. they don't know how to go upstairs

D. their parents don't always go upstairs with them

3. If a child carries a heavy school bag, ______. [ ]

A. his back and neck will be hurt

B. his head and arms will be hurt

C. his hands will be hurt

D. his feed will be hurt

4. According to the doctor, Scott Bautch, if a child in Grade 5 weigh about 30 kilos, the school bag he carries

    should not be over ______. [ ]

A. 5 kilos

B. 3 kilos

C. 5.5kilos

D. 4.5 kilos

5. Some students thinks the best answer to this problem is that ______. [ ]

A .they should have a little homework to do after they got home

B. their teacher had better not ask them to do any homework

C. they should only take home library books they will read at night

D. they should use thin workbooks instead of thick books

下列科技成就给宗教神学以致命打击的有

①哥白尼的日心说②牛顿的经典力学③达尔文的生物进化论④爱迪生发明电灯泡[ ]

A．①②③④

B．①②③

C．①③

D．②④

统计资料显示，自改革开放以来，中国经济得到快速发展，老百姓也积累了越来越多的财富，当前居民储蓄在15万亿元左右。而随着股市等金融市场的繁荣，百姓投资理财热情高涨，到年10月初，沪深两市投资者开户数超过1.2亿户；基金资产净值总计已超过3万亿元，基金投资账户数超过9000万个。

（1）居民个人投资主要有哪些方式？（3分）

（2）如果你是一名投资者，你认为在选择投资方向时，应注意哪些问题？（8分）

三相异步电动机再生制动时，定子绕组中流过（）。

A、高压电

B、三相交流电

C、直流电

D、单相交流电

《种树郭橐驼传》概括文章的中心思想。