[填空题]
The following cumulative frequency diagram shows the distanc/m6a t0nr.oz ve students need tomjpu o0xok -i83- a/cv travel to get to sov/0ikj-8- 3aoum cx pchool.
1. Find the median distance a student travels to school.
2. Find the number of students that travel between 2 $\mathrm{~km}$ and 4 $\mathrm{~km}$ to get to school.
3. Find the percentage of students that travel more than 4.5 $\mathrm{~km}$ to get to school. %