CEMC Pascal, 2011

Geometry Difficulty 3.0 AMC 10/12 Find the answer Canada

Two circles are centred at the origin, as shown. The point $P(8, 6)$ is on the larger circle and the point $S(0, k)$ is on the smaller circle. If $QR = 3$ , what is the value of $k$ ?

(A) $3.5$ (B) $4$ (C) $6$ (D) $6.5$ (E) $7$

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