Because AB=8

So AC=BC=4

So PC=CA+AP=4+3=7.

In triangular POC, CO2=PO2-PC2?

(2? It means square)

Carbon dioxide =64-49= 15

(2? It means square)

Connecting AO

In the triangular AOC

(2? It means square)

AO2 = CO2 +AC2

= 15+ 16=3 1

So the radius AO= root number 3 1.

Sin & ltAPO=CO/PO (root number 15)/8