A ship sails from a port P P\,P on a bearing of 070° 070°\,070° for 12 km to a point QQQ.
It then sails on a bearing of 145° 145°\,145° for 9 km to a point RRR.
Show that angle PQR=105°PQR = 105°PQR=105°.
Find the distance PRPRPR, giving your answer to 3 significant figures.