The number of hours spent by a school student on various activities on a particular day is given below. Find the central angles and answer the questions that follow:
| Activity | School | Homework | Play | Travel to school | Watching TV |
| Number of hours | 7 | 2 | 1 | \(1\) | 7 |
What is the angle difference between the number of hours spent on homework and the number of hours spent playing?
The angle difference is \(^\circ\).