Athletic Field 1 Helpful formulas: 9 Area of Circle: A = 7:? Circumference of Circle: C = 21w \"Note: If you are working on a problem in the homework and you don't Know the formula, just 'Google' it! Make sure you Know these formulas for the unit test. An athletic field is designed as a rectangle with a semicircle at each end. The total perimeter of the field is 400 meters. a. Express the area ofthe field as a function in terms of the radius, r'. ofthe semicircles. Solution: Let's start by labeling the picture. If the radius of the top semicircle is r, what is the length of its perimeter (circumference)? Submit your answer below as an expression in terms of r. Note: Typing "pi" produces the pi symbol