The above figure shows the parallel banks of a straight stretch of river.
Starting from the point \(A\) on a bank, a man swims at an angle of \(40°\) with the bank, reaching a point \(B\) on the opposite bank after swimming \(150\) yd. A second swimmer also leaves the bank at \(A\) but reaches the opposite bank at \(C\). If \(BC = 50\) yd., calculate
- the width of the river;
- the angle between \(AB\) and \(AC\).