I found this questions asking how to do this in many different forums, so I will describe here how to implement a solution using PHP and AJAX.
The logical flow for the problem should be:
Write an event handler for the first drop down box to get …
The viewer will learn the benefit of using external CSS files and the relationship between class and ID selectors.
Create your external css file by saving it as style.css then set up your style tags:
Reference the nav tag and set your prop…