A、By collections made at City Hall. B、By donations from the participants. C、By the allocation of funds from local hospitals. D、B

W: Hey, Joe, what’s all this talk about the benefit walkathon this weekend?
M: Don’t you know, most of the residents in Packer Hall are going to try to walk the seven miles from the engineering library, across campus and down to city hall, in an effort to raise money for the new children’s hospital?
W: Sounds like a good idea. But I don’t understand where the money comes from.
M: Well, a few days before the walkathon, each participant goes around asking people to pledge just a certain amount of money for each mile that he or she expects to walk in the event. Then after the walkathon’s over, the participants go back to those same people, collect the money pledged and send it into the hospital.
W: So you mean if someone pledges, say, a dollar a mile, and you walk five miles, you get five dollars?
M: That’s right. Of course, most of my friends aren’t such big spenders, the biggest pledge I’ve gotten so far is 25 cents a mile,
W: And how many people have made pledges for you?
M: Eleven so far. Say, how about making it an even dozen?
W: Sure. If you do the same for me, the walkathon sounds like a perfect opportunity for me to break in my new pair of sport shoes.
Questions 16 - 20 are based on the passage you have just heard.
16. Who is going to participate in the walkathon?
17. How was money raised in the walkathon?
18. What is known about the course of the walkathon?
19. For what reason Joe does love to join in walkathon?
20. How much money has each of Joe’s friends pledged to him?