Having issues solving this problem:

13. The graph below shows the distance of an air- plane from an airport during a long flight. (a) How far was the airplane from the airport at 1 p.m.? At 2 p.m.? (b) How fast was the distance changing at 1 p.m.? (c) How could the distance from the plane to the airport remain unchanged from 1:45 p.m. until 2:30 p.m. without the airplane falling? 400 distance (miles) 300 200 100 1 PM 2 A - time