[填空题]
The following cumulatib(qq o/i: :0l;dsgwkw vqqeb-z/4m a1n e frequency diagram shows the distance students need to travel to get to schqq/na4e- m1bz ool.
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. %