A solid is a
three-dimensional figure. For example, a house brick is a solid, as
it is a three-dimensional figure.

Many of the solids we come across in our world are combinations of
special types of three-dimensional figures such as prisms, cylinders,
pyramids, cones and spheres. Measurement of surface area is very
important to us if we are concerned with the quantities of materials to be
used to cover the surface area.

The sum of the areas of all external surfaces of a three-dimensional
object is called its total surface area (TSA).

Total Surface Area of a Cube

Recall:

The total surface area (TSA) of a cube is the sum
of the areas of its six faces. That is:

Example 25

Find the total surface area of a box whose edges are all 3.5 cm long.