direction of flow

Problem 10
The diameter of a pipe carrying water changes gradually from 150 mm at A to 450 mm at B. A is 4.5 m lower than B. If the pressure at A is 70 kPa and that B is 50 kPa, when 140 L/s is flowing.
(a) Determine the direction of flow.
(b) Find the frictional loss between the two points.