A person travels by car from one city to another with different constant speeds between pairs of cities. She drives for 30.0 min at 85.0 km/h, 7.0 min at 70.0 km/h and 50.0 min at 60.0 km/h, and spends 40.0 min eating lunch and buying gas.
(a) Determine the average speed for the trip.
(b) Determine the distance between the initial and final cities along this route.