Given height off frustum cone = 16cm
Diameter of lower end of bucket (d1) = 16cm
Lower and radius (r1) = 16/2 = 8cm
Upper and radius (r2) = 40/2 = 20cm
Let ‘l’ be slant height of frustum of cone
Slant height of frustum cone (l) = 20cm
Curved surface area of frustum cone