Hiding buttons on pages

Hi again Xerte community,
Re: hiding buttons on Xerte pages
Colleagues on occassions wish to hide buttons, eg on Decision Tree page type
to hide all the buttons or...
$("#backBtn, #fwdBtn").hide();
...to leave the refresh button

Or to hide buttons on Quiz
$ ("#nextBtn, #restartBtn") . hide() ;

What code do I use please to hide the Check Answers button on the Categories page type?
I tried the following:

$ ("#checkanswers") . hide() ;

But that didn't work.

I look forward to hearing from you as to whether I can do this, and what code I use to hide the Check Answers button.

Thanks in advance for your help.

Anne