Problem
Practice writing event handlers.
a. Write the XHTML tag and event handler to pop up an alert message that says "Welcome" when the user clicks a button.
b. Write the XHTML tag and event handler to pop up an alert message that says "Welcome" when the user moves the mouse pointer over a hypertext link that says "Hover for a welcome message".
c. Write the XHTML tag and event handler to pop up an alert message that says "Welcome" when the user moves the mouse pointer away from a hypertext link that says "Move your mouse pointer here for a welcome message".