At 11 43, Cathy started driving at 86 km/h from her home to a supermarket 43 km away. She was at the supermarket for 2 h 34 min.
- What time did she leave the supermarket?
- After leaving the supermarket, Cathy drove back along the same route and took 40 min to reach home. What was her average speed, in km/h, for the journey home?