Miss Rogers taught physics in a New York school. Last month she was explaining to one of her classes about sound, and she decided to test them to see how successful she had been in her explanation. She said to them, "Now, I have a brother in Los Angeles. If I was calling him on the phone, and at the same time you were 75 feet away, listening to me from the across the street, which of you would hear what I said earlier, my brother or you—and for what reason?"

The smartest student at once answered, "Your brother, Miss Rogers, because electricity travels faster than sound waves."

"That's very good," Miss Rogers answered; but then one of the girls raised her hand, and Miss Rogers said, "Yes, Debbie?" "I disagree," Debbie said. "Your brother would hear you earlier because when it's eleven o'clock here, it's only eight o'clock in Los Angeles."

A   Answer these questions:

1. What was the class in this story studying?
2. What question did Miss Rogers ask her class?
3. What did the smartest student answer?
4. What did Miss Rogers answer?
5. What happened then?
6. What did Debbie say?

B    Which of these sentences are true? Write down the correct ones.

1. Miss Rogers was teaching her class to hear sounds.
2. Miss Rogers was teaching her class about sound.
3. She wanted to know which were faster, sound waves or electricity.
4. She wanted to know whether her students could hear her from 75 feet away.
5. She wanted to know whether it was possible to telephone Los Angeles.
6. The smartest student thought that sound waves were slower than electricity
7. The smartest student thought that electricity was slower than sound waves.
8. Miss Rogers agreed with the smartest student.
9. Miss Rogers disagreed with the smartest student.
10. Debbie thought the smartest student was wrong, because electricity was slower than sound waves.
11. Debbie thought the smartest student was wrong, because clocks in Los Angeles showed a different time from those in New York.
12. Debbie thought that the smartest student's answer was correct.

C     Write this story, putting one word in each blank space. You will find all the correct words in the story.

One of the things that students of ________ study is the way in which sound ______from one place to another through the air. It does this by means of _______. A picture of these helps very much in the _______ of how this happens. Most teachers are very ______ in_______ sound to their students, and the students usually have no trouble when the teachers give them a _______ to see how much they have understood. I think the ________ for this is that most students have seen waves on water, so they don't find it difficult to imagine waves in the air which carry a _________ from one place to another. I am sure that no teacher will ________ with this.