下列有关化学研究的正确说法是[ ] A.同时改变两个变量来研究反应速率的变化,能

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问题:

下列有关化学研究的正确说法是[ ]

A.同时改变两个变量来研究反应速率的变化,能更快得出有关规律

B.对于同一个化学反应,无论是一步完成还是分几步完成,其反应热是相同的

C.依据丁达尔现象可将分散系分为溶液、胶体与浊液

D.从HF、HCl、HBr、HI酸性递增的事实,推出F、Cl、Br、I的非金属性递增的规律

考点:盖斯定律溶液浊液胶体元素周期律
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阅读下面的短文,并根据短文后的要求答题(请注意问题后的字数要求)

How do you get to school every day? By bike, bus or car? In Chongqing, there will be 3,000 new school buses on the street by the end of this year. These school buses look just like tlic American school buses: yellow with a big nose.

In February 2010, the Chinese government announced the first standards (标淮)for school bus safety. Since then, more yellow school buses can be seen on the street.

In China, besides the bus driver, there should be an adult on the school bus to watch the students. If there are more than 40 students, two adults are needed. The students usually rest or read books on the school bus.

In America, yellow school buses are very popular. There are about 480,000 school buses in the country. The older kids sit in the back of the bus. The younger kids sit in the front. They usually listen to music, talk on their phones or just sleep. The only adult on the bus is the driver.

The school bus is important in students’ everyday lives. It can keep children safe. Usually a child is much safer going to school by school bus than any other way. It can also help the environment. A school bus saves a lot of gas (汽油)because it can carry a lot of people.

小题1:What color are the new school buses in Chongqing? (Please answer within 3 words.) 

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小题2:When did the Chinese government announce the first standards for school bus safety? (Please answer within 3 words.)

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小题3:How many adults are needed on a Chinese school bus if 45 kids are on it besides the driver? (Please answer within 4 words.)

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小题4:What do American kids usually do on their school buses? (Please answer within 12 words.)

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小题5:Why is the school bus important in students’ everyday lives? (Please answer within 12 words.)

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任意投影

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上尿路特异性和非特异性感染的尿液,称为()。

A.黏液性溢出物

B.血性溢出物

C.脓性溢出物

D.脓尿

E.乳糜尿

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He hardly had anything to eat, ________ he?

A.didn’t

B.hadn’t

C.was

D.did

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粮库温度在:18~21℃、相对湿度在65%以上时,适于虫卵孵化及害虫繁殖。( )

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