$\"\"$

Observe the solid figure, it is a cylinder.

The radius of the cylinder $\"\"$ and its height $\"\"$ .

The volume of the cylinder $\"\"$ .

The value of $\"\"$ substitute in the equation, $\"\"$ .

$\"\"$

Apply power of a product property: $\"\"$ .

$\"\"$ $\"\"$

Group the coefficient and the same variables.

$\"\"$

Apply product of powers property: $\"\"$ .

$\"\"$

The volume of the cylinder is a monomial, since this expression has product of two numbers and one variable with nonnegative integer exponents. \ \ $\"\"$

The monomial expression of volume of the cylinder $\"\"$ .