A、One year and a half. B、Less than four years. C、Roughly six years. D、About five years. D细节辨认题。女士说，普通家庭差不多五年就能收回最初的投资。

W: Rays Solar. Lisa’s speaking. How can I help?
M: Hi, my name is Winston. I wish to enquire about solar panel installations.
W: Yes. What would you like to know?
M: Well. My neighbor installed panels on his roof about a year ago in order to power his hot water. He tells me it has saved him over $500 thus far. Does that sound about right to you?
W: Well. I’m not familiar with your neighbor or his particular setup, but that amount is definitely possible. I can tell you that the average four-bedroom house may typically have a roof with 50 square meters of surface area. Four panels on one side of that roof could save a family of four around $300 a year.
M: OK. That sounds about right then. My house is about the size you described, but my neighbor’s is bigger. I’m not sure how many panels he has up there, but he does have a large family of six.
W: Are you interested in installing some solar panels on your roof, sir?
M: Yes, I’m considering it.
W: If you wish to come into our office, we could show you the different solutions we offer.
M: OK. I might do that. But just quickly, if you don’t mind, could you tell me approximately how much a typical installation costs, like, say, four panels?
W: Prices do vary depending on different factors, but as a rough estimate, it’s around $2,000. But you know a typical household will make back that initial investment in about five years.
M: OK. I see. Thank you.
Questions 8 to 11 are based on the conversation you have just heard.
8. What is the man’s purpose for calling the woman?
9. What do we learn about the man’s neighbor from the conversation?
10. What is one of the man’s chief concerns?
11. How long will it take a typical household to make back the initial investment?