In this question the unit vectors i\mathbf{i}i and j\mathbf{j}j are due east and due north respectively.
A coastguard station O O\,O monitors the movements of a small boat.
At 08:00 the boat is at the point (3i−4j)(3\mathbf{i} - 4\mathbf{j})(3i−4j) km relative to OOO.
At 10:20 the boat is at the point (−2i−7j)(-2\mathbf{i} - 7\mathbf{j})(−2i−7j) km relative to OOO.
The motion of the boat is modelled as that of a particle moving in a straight line at constant speed.
Calculate the bearing on which the boat is moving, giving your answer to 1 decimal place.
Calculate the speed of the boat, giving your answer in km h−1^{-1}−1 to 3 significant figures.