JavaScript Exercise 3 - Forms Exercise

Add JavaScript to a form so that when the user makes an entry or a selection in the form, what is displayed on the page changes.  You do not need to verify that the user makes a valid choice -- we will do this in a later exercise.  How the page changes when the user acts is up to you.  Examples of what you could do include the following:

1) When the user selects an item and a quantity, the total cost is displayed.  You could also compute and display additional charges, such as sales tax or shipping cost, and then display the total cost.

2) When the user makes a selection in a form, the choices available in another form element on the page change.  The code sample shows how to do this for a <select> element changing another <select> element.  Consider having at least one of the form elements involved be something other than a <select> element.