The interior of a building is in the form of a right circular cylinder of diameter 4.2 m and
Channel: Doubtnut
Date: 2020-04-19

The interior of a building is in the form of a right circular cylinder of diameter 4.2 m and height 4 m surmounted by a cone of same diameter. The height of the cone is 2.8 m. Find the outer surface area of the building.