Can someone help me understand this homework question better, I'm just not seeing at at all the way it's phrased.

see image for question.

Triangle CPQ is a right triangle with legs CP (= R) and PQ (= d) . CQ is the hypotenuse.

And we can use the tangent to find PQ.....we have that

tan ( θ/2) = PQ / R

tan (39/2) = d / 964 multiply both sides by 964

964 tan (19.5) = d ≈ 341.4 ft

Thanks