Arlene is showing her work in simplifying −7.9 + 8.2 − 3.4 + 2.1. identify any errors in her work or in her reasoning. write feedback to arlene explaining the mistake she made and how to correct her work.

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)