Case 1 :
Radius, r = 5 feet.
Area,
[tex]A=\pi r^2\\\\A = 3.14\times 5^2\ feet^2\\\\A = 78.5\ feet^2[/tex]
Case 2 :
Diameter, d = 56 mm.
So, radius, r = d/2 = 28 mm.
Area,
[tex]A = 3.14\times 28^2\ mm^2\\\\A = 2461.76\ mm^2[/tex]
Hence, this is the required solution.
