A corn cob shaped like a cone, has the radius of its broadest end as 1.4 cm and length (height) as 12 cm. If each` 1cm^(2)` of the surface of the cob carries an average of four grains, find how many grains approximately you would find on the entire cob.

Curved surface area of a cone is 308 cm^(2) and its slant height is 14 cm. Find radius of the base.

Curved surface area of a cone is 308 cm^(2) and its slant height is 14 cm. Find total surface area of the cone.

A right circular cone of height 8.4cm and the radius of its base is 2.1cm. It is melted and recast into a sphere. Find the radius of the sphere.

A right circular cylinder has base radius 14 cm and height 21 cm. Find its area of base (or area of each end)

The height of a right circular cylinder is 14 cm, and the radius of its base is 2 cm. Find its curved surface area .

Rachel, an engineering student, was asked to make a model shaped like a cylinder with two cones attached at its two ends by using a thin aluminum sheet. The diameter of the model is 3 cm and its length is 12 cm . If each cone has a height of 2cm , find the volume of air contained in the model that Rachel made . ( Assume of outer and inner dimensions of the model to be nearly the same .