题干

在甲、乙、丙三个培养皿中分别放入等量的面巾纸,在面巾纸的上面都放25粒绿豆种子,然后将它们放在不同条件下进行培养,数日后记录种子萌发的情况如表.

装置

温度

23℃

23℃

0℃

面巾纸干湿状态

潮湿(含一定量的水分)

干燥

潮湿(含一定量的水分)

种子萌发的数量

23

0

0

据表分析可知,该实验的实验变量是(  )

A:温度和光照

B:温度和水分

C:光照和水分

D:水分和氧气

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答案(点此获取答案解析)

B

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    Traveling to all corners of the world gets easier and easier. We live in a global village, but this doesn't mean that we all behave in the same way.

    How should you behave when you meet someone for the first time?____In Japan, you should bow, and the more respect you want to show, the deeper you should bow. In Thailand, people greet each other by pressing both hands together at the chest.____

    ____ In Muslim countries, you shouldn't expose your body, especially women, who should wear long blouses and skirts. In Korea, you should take off your shoes when entering a house. Remember to place them neatly together where you come in.

    In Spain, lunch is often the biggest meal of the day, and can last two or three hours.____ In Mexico, lunch is the time to relax, and many people prefer not to discuss business as they eat. In Britain, it's not unusual to have a business meeting over breakfast.

    In most countries, an exchange of business cards is necessary for all introductions. It should include your company name and your position. If you are going to a country where your language is not widely spoken, you can get the back side of your card printed in the local language.____

A. For this reason, many people eat a light breakfast and a late dinner.

B. As the saying goes, "when in Rome, do as the Romans do."

C. In both countries, eye contact is avoided as a sign of respect.

D. In China, you may present your card with the writing side up.

E. An American shakes your hand while looking into your eyes.

F. Many countries have rules about what you should and shouldn't wear.

G. Don't make any noise when you eat or drink soup.