Surface area of cone is a sum of surface of its base and surface of its mantle.
Surface of its base is a circle which surface we will calculate like this:
Sb = pi*r^2 where r is d/2
Sb = 201m^2
Surface of mantle we calculate by:
Sm = pi*l*r where l is length of side of cone.
l = [tex] \sqrt{r^2 + H^2} [/tex] = 25.3
Sm = 635.8m^2
Total suface is:
Sb + Sm = 836.8m^2
