17
A. History is more important than the other courses.
B. Chemistry is not popular with students.
C. Music is not a required course.
D. Every student has to study computer science.
18
A. Because it is useful.
Because it is enjoyable.
C. Because it is interesting.
D. Because it is very modern.
[音频]Questions 19 to 21 are based on the passage you have just heard.
A. Impulse Buying.
B. Self-Service Shopping.
C. The More Products, the More Confusion.
D. Psychologists and Merchandising Experts.
20
A. Only five percent of the shoppers decide in the store.
B. More than five shoppers make a list before shopping.
C. Nearly ten percent of the shoppers decide in the store.
D. Less than twenty percent of the shoppers make a complete list.
21
A. The clerks ignore the customers.
B. The clerks are too eager to serve the customers.
C. The stores have to send the shopper’s purchases to his home.
D. Customers hesitate to ask for help if they haven’t decided what to buy.
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