remove the emacs beep warnings

In my new installed linux system, I used emacs often. But soon i found it produces a beep sound everytime when there is some little situations arrive, for example, reaching the end of file. It is quite disturbing. I decide to remove this sound by modifying the .emacs.

In the .emacs file I added

(setq visible-bell t)

I also activate the function of setting mark:
(setq mark-even-if-inactive t)