In the figure, PQR is a semicircle while PQ and QR are chords. QS is the perpendicular from Q to the diameter PR. What is the expression for QS?
-
A.
QS = PS(sqrt{SR}) -
B.
QS = (sqrt{(PS SR)}) -
C.
QS = 2(sqrt{(PS SR)}) -
D.
QS = (frac{1}{sqrt{2}})(sqrt{(PS SR)})