With the same airspeed as in Problem 1.16, in what direction must the plane head in order to move due east relative to the Earth?

Problem 1.16

A plane is traveling eastward at an airspeed of 500 km/h. But a 90- km/h wind is blowing southward. What are the direction and speed of the plane relative to the ground? If you have not learned how to deal with relative velocities, skip this problem.