At 17 47, Kimberly started driving at 72 km/h from her home to a school 30 km away. She was at the school for 2 h 24 min.
- What time did she leave the school?
- After leaving the school, Kimberly drove back along the same route and took 30 min to reach home. What was her average speed, in km/h, for the journey home?