A boat travels from south bank to north bank of a river with a maximum speed of 8 km/h. To arrive at a point opposite to the point of start, the boat should start at anangle

In order to arrive at the opposite bank, the boat should start at an angle θ with north such that sin⁡θ=48 or θ=30∘. The real velocity of boat will be          v=82−42=48,θ=30∘W of N