An aeroplane has to go from a point A to another point B, `500 km` away due `30^@` east of north. Wind is blowing due north at a speed of `20 m//s.` The steering-speed of the plane is `150 m//s.` (a) Find the direction in which the pilot should head the plane to reach the point B. (b) Find the time taken by the plane to go fram A to B.