Australian AMC 2011 - Junior Question 15

Question 15

In the diagram, $PT$ divides $\angle RPQ$ in half and $SQ$ divides $\angle PQR$ in half. $\angle PRQ=60^\circ$. What is the size of $\angle SUP$?

Question illustration

$75^\circ$
$60^\circ$
$45^\circ$
$40^\circ$
$30^\circ$