Will the program work if the user enters a zero?

A good answer might be:

Hmmm... it should, since zero has a square root.

Example Output

It is good to get into the habit of worrying about what happens with special values. The program does happen to work with zero. Here is the output of the program for several values: 

C:\chap19>java SquareRoot
Enter the number:
0.0000000000000000000003
The square root of 3.0E-22 is 1.732050807568877E-11

C:\chap19>java SquareRoot
Enter the number:
-12
Please enter a positive number

C:\chap19>java SquareRoot
Enter the number:
144.0
The square root of 144.0 is 12.0

QUESTION 20:

Suggest a few other values with which the program should be tested.