Question
Get the cylinder class from the base circle class. Suppose the circle class has a protected member variable representing the radius known as radius and declared as a double with a default value of 1.0. It also has a public function known as calcVal that evaluates the area of a circle as PI *
radius * radius where PI is a constant 3.14.
In your derived class contain an additional protected member representing length of the cylinder. Call this variable length. Have the default values for the cylinder class is 1 for both the radius and the length. For this derived cylinder class contain a public function calcVal that evaluates volume of the cylinder.