To indirectly measure the distance across a lake, Zahra makes use of a couple landmarks at points O and P....

To indirectly measure the distance across a lake, Zahra makes use of a couple landmarks at points O and P. She measures NQ, QO, and QR as marked. Find the distance across the lake (OP), rounding your answer to the nearest hundredth of a meter.
Diagram labels: QO = 140 m, NQ = 145 m, QR = 84.8 m. Right angles are marked at O and Q.
(Diagram is not to scale.)