题干

已知f:x→x2是集合A到集合B={0,1,4}的一个映射,则集合A中的元素个数最多有(   )

A:3个

B:4个

C:5个

D:6个

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C

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信息匹配。

School BBS   About life in England

A: Many English people live in houses, not in apartments. Most houses have gardens. Many young people don't live with their parents.

B: School starts at about nine o'clock in the morning and finishes at about three o'clock in the afternoon. All the children go to school when they are four or five years old.

C: Most office workers start to work at about nine in the morning, and finish work at about five or six in the afternoon. Most people don't go home for lunch, and they just have a quick meal!

D: Most shops open at about nine o'clock in the morning and close at about eight o'clock in the evening. People can buy fast food or life things in the shops.

E: In the evenings, I usually do my homework before watching TV. Mum helps me with my homework. My family like to watch Coronation Street (an English soap opera).

F: The second most popular activity in England is visiting friends or relatives. Mum and Dad go out and visit friends at least once a week.

①They usually go to work by bus, and they work with computers. ____

②I have to help Mum wash the dishes after meals. I also have to clean my bedroom. ____

③On weekends, many families go to the open market. People sell vegetables, clothes, toys, and anything else out on the street. ____

④Most families have a car, a computer, a washing machine, etc. Almost everyone has a mobile phone. ____

⑤Most children take a lunch box to school. There are usually things like sandwiches, fruit and a bag of French fries in it. ____