10. According to the author, when will the problems to explore the deeper sea largely be solved?
　　A. In the next generation.
　　B. By the end of the 20th century.
　　C. In the near future.
　　D. By the middle of the 21st century. Passage 3

　　estions 11 to 15 are based on the following passage:

　　Today, cigarette smoking is a common habit. About forty-three percent of the adult men and thirty-one percent of the adult women in the United States smoke cigarettes regularly. It is encouraging to see that millions of people have given up smoking.

　　It is a fact that men as a group smoke more than women. Among both men and women the age group with the highest proportion of smokers is 24-44.

　　Income, education, and occupation all play a part in determining a person's smoking habit. City people smoke more than people living on farms. Well-educated men with high incomes are less likely to smoke cigarettes than men with fewer years of schooling and lower incomes. On the other hand, if a well-educated man with a higher income smoked at all, he is likely to smoke more packs of cigarettes per day.

　　The situation is somewhat different for women.（80）There are slightly more smokers among women with higher family income and higher education than among the lower income and lower educational groups. These more highly educated women tend to smoke more heavily.

　　Among teenagers the picture is similar. There are fewer teenaged smokers from upper-income, well-educated families, and fewer from families living in farm areas. Children are most likely to start smoking if one or both of their parents smoke.

　　11. What do we know from the first paragraph ?
　　A. More and more people take up the habit of smoking.
　　B. There are more smoking women than smoking men in USA.
　　C. It is good news that more people have given up smoking.
　　D. The U.S. has more smoking people than any other country.

　　12.What factors determine a person's smoking habits ?
　　A. Age, income and education.
　　B. Age, sex and income.
　　C. Occupation, income and sex.
　　D. Occupation, income and education.

　　13.Which of the following is true according to the passage ?
　　A. City people are less likely to smoke.
　　B. People in rural areas are more likely to smoke.
　　C. Men with higher income tend to smoke.
　　D. Well-educated men with high incomes are generally less likely to smoke.

　　14.What is the smoking situation for women ?
　　A. The situation is quite the same for women as for men .
　　B. Better-educated women are likely to smoke heavily.
　　C. There are more women smokers with low incomes.
　　D. Women with higher incomes and higher education do not tend to smoke.

　　15.What can we say about teenaged smokers ?
　　A. The picture about the teenage smokers is similar to that of women smokers.