Answer:
d. 11.3 cm
Explanation:
The radius of the circle is the length CP, which can be found using the Pythagorean theorem. Since CQ ⊥ PR, you know that Q is the midpoint of PR and PQ = 8 cm.
Then the Pythagorean theorem tells you ...
CP² = CQ² +PQ² = (8 cm)² + (8 cm)² = 128 cm²
CP = √128 cm = 8√2 cm
CP = 11.3 cm