Question

the interior of a building is in a form of cylinder of base radius 12 m height 3.5 M terminated by a cone of equal base and slant height 13 M find the internal surface area of building

Answer 1

area is equal to surface area of cylinder and of cone so
$(2 \times \pi \times 12 \times 3.5) + (\pi \times 12 \times 13)$