The Program in C# Sharp program that takes the radius of a circle as input and calculates the perimeter and area of the circle given below:

using System;

namespace CircleCalculator
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Hello Codeauri Family, enter the radius of the circle to find perimeter and area of circle:");
            double radius = Convert.ToDouble(Console.ReadLine());

            double perimeter = 2 * Math.PI * radius;
            double area = Math.PI * Math.Pow(radius, 2);

            Console.WriteLine("Well, the perimeter of the circle is: " + perimeter);
            Console.WriteLine("Well,the area of the circle is: " + area);
        }
    }
}

Output:

Hello Codeauri Family, enter the radius of the circle to find perimeter and area of circle:7
Well, the perimeter of the circle is: 43.9822971502571Well,the area of the circle is: 153.9380400259

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Here are the step by step execution of above program:

1. The using System; statement is a directive that tells the compiler to include the System namespace in the program.
2. The namespace CircleCalculator defines a namespace that encapsulates the Program class.
3. The class Program contains a Main method, which is the entry point of the application.
4. The Main method starts by displaying a message asking the user to enter the radius of the circle.
5. The user’s input is converted to a double using the Convert.ToDouble() method and stored in a variable called “radius”.
6. The perimeter of the circle is calculated using the formula 2 * Math.PI * radius.
7. The area of the circle is calculated using the formula Math.PI * Math.Pow(radius, 2).
8. Finally, the perimeter and area of the circle are displayed to the user using Console.WriteLine().