Compute all parts of given question:
Question: An airplane maintains a speed of 645 km/h relative to the air it is flying through as it makes a trip to a city 745 km away to the north. (Assume north is the positive y-direction and east is the positive x-direction.)
Part A: What time interval is required for the trip if the plane flies through a headwind blowing at 32.1 km/h toward the south?
Part B: What time interval is required if there is a tailwind with the same speed?
Part C: What time interval is required if there is a crosswind blowing at 32.1 km/h to the east relative to the ground?
Show how you get the answer, so that I can better understand how to do it.