若方程5x²ⁿ⁺¹=1是一元一次方程，则n等于（　　）

根据短文理解，选择正确答案。

    There are fifty students in our class. There are twenty-four boys and twenty-six girls. Some students live near the school, and some others live far from school. About half of the students usually come to school by bike. They often get to school at a quarter to seven. About fifteen students often come to school by bus. They often get to school very early, too. Another ten students come to school on foot. Their homes are near the school, but they are often late for school, because they get up late.

在地理信息系统中，存储和处理的数据根据内容可分成基础数据和专题数据两大类。其中属于专题数据的是(　　)