Find the intersection of the three sets: a = {–2, 7, 8, 11}, b = {–2, 7, 11}, c = {–2, 8, 11}. {–2, 7, 8, 11} {–2, 7, 11} {–2, 11} {11}

Circle a has a diameter of 7 inches, a circumference of 21.98 inches, and an area of 38.465 square inches. the diameter of circle b is 6 inches, the circumference is 18.84 inches, and the area is 28.26 square inches. part a: using the formula for circumference, solve for the value of pi for each circle. (4 points) part b: use the formula for area and solve for the value of pi for each circle. (4 points)