听力原文：W: Hey, Tom! I heard that you are auditing at the history class. How do you like it? M: Pretty good! Prof. Lincoln talked a lot about Africa yesterday. (13) Do you know which African country has the strongest economy? W: (13) I would guess South Africa. It's probably got the most modern infrastructure of all the African countries. M: (13) Exactly! And Prof. Lincoln said that it is one of the most stable democracies in that part of the world. W: Sounds interesting. What else did Prof. Lincoln say? M: As developed as it is now, that's not to say that there haven't been problems. I bet you can guess what I'm referring to. W: Apartheid? M: Yes, under apartheid, the government maintained a policy of separating the white minority and the black majority. (14) Early on, black people were barred from being members of parliament. It was a whites-only government. W: Does everyone speak English in South Africa? M: No, not necessarily. Most people do, but there are actually eleven official languages. English is one. The most commonly spoken language that's native to the area would be Zulu. W: And... And how about the population there? M: Interestingly, South Africa has the largest population of people of European descent in Africa, and the largest Indian population outside of Asia. Not only that, (15) it also has the largest mixed race community in Africa. W: Oh, you really know a lot about that country now! I guess I want to audit at the history class next semester. M: I bet you won't regret it. 13. According to the conversation, what is the situation about South Africa? 14.What does the man say about the black people under apartheid? 15.What can we learn about South Africa from the conversation? (1)