Help but please if you don't know the answer or not sure dont write anything

Answer:
16.5
Step-by-step explanation:
PQ = PR ⇒ PQ = 13.2
Angle OQP = 90° therefore using Pythagoras' theorem:
OQ² + PQ² = OP²
9.9² + 13.2² = OP²
272.25 = OP²
OP = √272.25 = 16.5