Answer:(200π - 12)ftor616.32 ftStep-by-step explanation:Given in the question,there are four circle around which corn will be planted.radius of first circle = 10 ft radius of second circle = 20 ftradius of third circle = 30 ft radius of fourth circle = 40ft circumference = 2πrFirst circle2π(10)-320π -3Second circle2π(20)-340π-3Third circle2π(30)-360π-3Fourth circle2π(40)-380π-3Add them up80π - 3 + 60π - 3 + 40π - 3 + 20π - 3(200π - 12)ftor616.32 ft