Why some Jqueries work and some don't?

Why some Jqueries work and some don't?

Hi;

I have a page with lots and lots of Jqueries but only some of them work!

What I can tell is that Jquery is being loaded and accessible by the page.

The page is HERE.

For example when I click on <a id = "rubber">   (the  RUBBER button), it should change the value of the text box above but it doesn't.

It's in line 400 of my code:

  1.  //Rubber  $('#rubber').click(function() {  $('#buttonStyle_DB').val('2');  }); 


Thanks for help.