In the figure, $PA$ is tangent to semicircle $SAR$, $PB$ is tangent to semicircle $RBT$, and $SRT$ is a straight line. If arc $AS$ is $58^\c

In the figure, PA is tangent to semicircle SAR, PB is tangent to semicircle RBT, and SRT is a straight line. If arc AS is 58 degrees and arc BT is 37 degrees, then find angle APB, in degrees.