Question

if the diameter of the base of a closed right circular cylinder be equal to its height 'h' , then its surface area is

Answer 1

Height = h
Diameter = h
radius = h/2

Surface area = curved surface area + area of base and top
                    = 2πrh + 2πr²
                    = 2πr(r+h)
                    =2×π×h/2( h+h/2)
                    = πh(3h/2)
                    =3πh²/2

Answer 2

for cylinder'
Height(h)=diameter=2radius
so,
h=2r
total surface area =2πr(r+h)
                             =2πr(3r)
                             =6πr²
and c
Curved surface area=2πrh
                                 =4πr²