Simple inclass exercise for week of January 21

We all know that the area of a circle of a given radius r is (pi * radius * radius). Write a complete java program that will prompt the user
to enter a radius and will outpur the area of the given circle of that radius.

A few features your program must include:

1) Sine the value of Pi doesn't change much, we will declare a constant!! How does one do this ?? You could look in section 1.4.
But I will help:

    Before your "public static void main" but AFTER "public class YourClassName" type the following:

    public static final double PI = 3.14159;          // for all intensive purposes, we will call this a constant

    A few things to note:
    - by using the modifer "final", you will not be able to modify the value of the variable PI in your program. You must verify this and show your results
       to either me or the lab master
    - by convention, constants in Java should use all capital letters. It makes it easy to spot.

2) Here is a sample output of how the program should execute. Your program must match exactly:

        Enter the radius 23.5
        The area of the cricle of radius   23.50 is 1734.9410

The program prompted for "Enter the radius" and then the cursor remained on the same line. The user typed 23.5 and return. The program responded
with the second line. Please note that all floating point values show 2 digits past the decimal point. You will need to use the System.out.printf command.

You must demo your program

IMPORTANT
Your program is not complte until:
    it contains a heading with your name
    it contains comments about what the program does
    it employs descriptive variable names (not like 'x' or 'y')