30.A airplane maintains a speed of 573 km/h relative to the air
it is flying through as it makes a trip to a city 766 km away to
the north. (Assume north is the positive y-direction and east is
the positive x-direction.) (a) What time interval is required for
the trip if the plane flies through a headwind blowing at 35.1 km/h
toward the south? h (b) What time interval is required if there is
a tailwind with the same speed? h (c) What time interval is
required if there is a crosswind blowing at 35.1 km/h to the east
relative to the ground?