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    <title>Document</title>
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    <script>
        // Create a simple function with name firstFunction().
        // and stored the value in console ('This is my first function')
        // and call the function firstFunction().

        function firstFunction() {
            console.log("This is my first function");
        }
        firstFunction();

        //       Create a function with name square().
        // The function square() takes one parameter and parameter name is num.
        // Return the parameter (num) multiplied by itself. Example like (num * num)
        // and call the function square() and store the result in console.

        function square(num) {
            return num * num;
        }
        console.log(square(8));

        // Create a one function with name is Addition()
        // The function Addition() takes Four parameter like num1,num2,num3,num4.
        // take a one variable in function that is result and stored the addition of this four paramater in the result
        // Resturn the result variable under the function
        // and now call the Addition() function

        function Addition(num1, num2, num3, num4) {
            result = num1 + num2 + num3 + num4;
            return result;
        }
        Addition(10, 20, 30, 90);
        // alert(Addition(10, 20, 30, 90));
        // console.log(Addition(10, 20, 30, 90));
    </script>
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