please use << PHP >>

Program 1 Create an HTML page with a form that displays a drop list with four options. When the form is submitted, a PHP file uses if...elseif...else blocks to generate a response to the option selected. See Sample Output next.

Program 2 Create another virtually identical HTML file, but make it execute a different PHP file. This second PHP should generate exactly the same output as above, but it must use a switch.

Program 3 Write a program that uses nested loops to generate a right triangle exactly as shown next: o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o