12 Salman and Aloke are hiking on a flat level ground. Their starting point is taken as the origin and the unit vectors i and j are in the directions east and north. Salman walks with constant velocity 3i + 6j kilometres per hour. Aloke walks on a compass bearing of 300° at a steady speed of 6.5 kilometres per hour.

i Who is walking fastest and by how much? i How far apart are they after 1½ hours?