题目内容

设关系R和关系S的元数分别是3和4，关系T是R与S的广义笛卡尔积，即：T：RxS，则关系T的元数是(22)。

A. 7
B. 9
C. 12
D. 16

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【C5】

A. yielding to
B. submit to
C. subdue
D. yielding

A．drawingB．mappingC．picturingD．scanning

A. drawing
B. mapping
C. picturing
D. scanning

听力原文： (Ring... ring... Sound of phone being picked up. )
M: Hello, Campus Daily, advertising department. This is Mark speaking.
F: Hi. I' m calling to place a couple of ads.
M: Sure. Under what classification？
F: Well, I want one in the" Roommate Wanted" section.
M: All fight. And how would you like that to read？
F: Ok, it should read Female roommate wanted for pleas-ant, sunny two, bedroom apartment on Eliiewood Avenue, three blocks from campus. Share rent and utilities. Available September 1. Call between 5 and 9 P.
M: and ask for Celilia.
M: Fine. And what about your other ad？
F: That one I'd like under "Merchandise for Sale," and I'd like it to read "Matching blue and white sofa and easy chair, excellent condition, $ 350 or best oiler. Call between 5 and 9 P. M. and ask for Cecilia." Did you get all that？
M: Uh-huh. You'll want your phone numbers on these, right？
F: Oh, sure. Thanks for reminding me——it's 555-6972.
M: And how long do you want these ads to run？
F: For a week, I suppose. How much would that be？
M: It's five dollars a week per line. Each of your ads will take up three lines, so that's $15 per ad .
Where does Mark work？

At a newspaper.
B. At an advertising agency.
C. At a furniture store.
D. At a real estate office.

听力原文：F: Good morning, Andy.
M: Good morning Jessie. What can I do for you？
F: Look, several days ago, I changed my job to be a trainer in a big company. And I suddenly feel uncomfortable with my present hairstyle.
M: How come？
F: You see, the trainees regard me as their teacher and respect me very much. But my boss is not satisfied with my hairstyle. He said I look too naive with this hairstyle. And also I' m terribly busy with my work, so I can hardly have time to look after such long hair of mine.
M: I see. Yes, you have a bang that usually makes one look younger than they are. So does your ponytail and hair clips.
F: That' s exactly what my boss said to me. So I want to make a change. Can you give some advice？
M: What about having your hair cut short？ It will make you look more matured and more professional. To be a trainer, you need to make people trust you at the first sight. I will give you a magazine. You can chose one from the many hairstyles in it.
F: Thanks. Do you have any good ways to keep my hair healthy？
M: Fist of all, you should eat a balanced diet and get plenty of exercise. Look after your hair at home. City air is dirty and polluted, so it would be wise for you to shampoo your hair frequently. After shampooing, dry your hair gently with a towel before using the hair dryer. Always set it at a low temperature and hole it at least 10em from your hair.
F: Thanks you Andy.
Why does Jessie want to change her hair style？

A. She has found a job.
B. She has become a teacher.
C. Her boss is dissatisfied with her hairstyle.
D. All of the above.