Performs arithmetic operations on two numbers
30
?operation=add&a=10&b=20 → Addition
?operation=add&a=10&b=20
?operation=subtract&a=50&b=15 → Subtraction
?operation=subtract&a=50&b=15
?operation=multiply&a=7&b=8 → Multiplication
?operation=multiply&a=7&b=8
?operation=divide&a=100&b=5 → Division
?operation=divide&a=100&b=5
