Bottom area: S 1=πR square =3. 14*(4/2) square =6.28 square centimeters.
The peripheral area is equal to the perimeter of the bottom surface multiplied by the height of the cylinder.
Outer circumferential area: S2 = π dl = 3.14 * 4 * 450 = 5652cm2.
The total surface area of the cylinder is: s = 2s1+S2 = 6.28 * 2+5652 = 5664.56cm2..
2. According to the surface area calculation formula of the problem 1, we can know that:
S 1=πR square = π d square /4, perimeter = π d.
So the diameter d = 45.2/3.14 =14.39 cm.
Bottom area: s1= 3.14 *14.39 square /4= 162.55 square centimeter.
Peripheral area: S2= perimeter * height =45.2*40= 1808 cm2.
Surface area of cylinder: s = 2s1+S2 = 2133.1cm2.