Two swimmers cross a river - can we calculate its width?

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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

1. the width of the river;
2. the angle between \(AB\) and \(AC\).