A、The public telephones often go wrong in malting a long distance call. B、It is not very expensive to make a long distance call

Telephone books in the United States have white, blue and yellow pages.
    The white pages list people with phones by last name. The blue pages contain numbers of city services, government agencies, and public schools. Business and professional services are listed in a special section--the Yellow Pages.
    To make a long distance call, you need an area code. Each area in the U. S. has an area code. The area covered by one area code may be small or large. For example, New York City has one area code, but so does the whole state of Oregon. If you want to know the area code of a place, you can look it up in the area code map, which is printed in the front of the white pages.
    There are a lot of public telephones in the U. S. They have their own numbers. If you are making a long distance call on a public telephone and run out of money, give the number on your phone to the person you’re talking with. Then hang up the receiver and he can call you back. If you make a long distance call and get a wrong number, call the operator and explain what happened. This means that you can make the call again to the right number without having to pay more money.
29. Where can you find the telephone number of a public school in the telephone book?
30.Where can you find the area code of Washington City?
31.Which of the following is true according to the passage?