C R The rectangle R has a length of 15 units and a width of 5 units. The point C is the center of the square S which measures 12 units on each side. The isosceles triangle T' has a base 2 units long and an altitude of 6 units. What is the midpoint of the line segment joining P and C'? (6.5, 17) O (6.5, 16) O (6, 17) (6, 16)