阅读理解。 Two men were sitting together in a plane.  They were on a long journey (旅行).One of them was a teacher. The other was a farmer. They sat without talking for a while, then the farmer said, Let's do something to pass the time.' 'What do you want to do?' the teacher asked. 'We can ask each other riddles,' said.the farmer. 'Let's make the rules first,' the teacher said. 'And let's make the game moreinteresting.  Let's play it for money.  If we don't know the answer to a riddle,  we have to pay $ 50. ' The farmer thought about this for a while, then he said. 'That's not fair. You are a teacher,  an educated man. You know more things than I do. I am just a farmer.' 'That's true, ' the teacher said, 'What do you think we should do?' 'If you do not know the answer to a riddle,  you pay me $ 100. If I do not know the answer to a riddLe,  I will pay you $ 50. ' the farmer said. The teacher thought about this, then he said, 'OK, that's fair. Who will go first?' 'I will,' the farmer said, 'Here's my riddle. What has three legs when it walks, but only two legs when it flies?' The teacher repeated the riddle, 'What has three legs when it walks, but only two legs when it flies? Mm, that's a good one. I'm afraid I don't know the answer.' He gave the farmer $ 100, then said, 'Tell me the answer. What has three legs when it walks, but only two legs when it flies?' 'I don't know.' the farmer said,  and gave the  teacher $ 50. 1. Two men were sitting in an airplane __ . A. on their journey home B. on their way to a farm C. on a long journey D. on their way to school 2. They decided to pass the time by ____ . A. reading the newspaper B. asking each other riddles C. playing cards D. talking about their families 3. If the farmer didn't know the answer to a riddle, he had to pay the teacher ___ . A. $50 B. $100 C. $200 D. $l 4. A teacher is ___ than a farmer. A. well-educated B. poor-educated C. better-educated D. worse-educated 5. In the end, the teacher paid the farmer __ . A. $50 B. $150 C. nothing D. $200