A man, rowing a boat, covers a distance of 16 km in two hours downstream. He covers half the distance in same amount of time when rowing upstream. Calculate the speed of the stream.
A flock of migrating geese flies 20 km East, then turns South and flies 50 km, then turns East and flies 40 km, and turns to its left and flies 50 km. Where is the flock now with reference to its starting position?