A person travels by car from one city to another with different constant speeds between the pairs of cities. She drives for 30.. min at 80.0 km/h, 12.0 min at 100 km/h, and 45.0 min at 40.0 km/h, and spends 15.0 min eating lunch and buying gas.
What is the average speed for the trip?
What is the distance between the initial and final cities along this route?