题目

单项填空 – Hi Peter. Do you know Oxford?    -Yes. It is ______ university in England. ______ university is world-famous. A. a; A                B. a; The                            C. an; The         D. an; An 答案：B用“四舍五入”法改写下面各数．2830750000≈2828亿         649086≈6565万．