Where is that damn nitro button?

Hi guys. Its been so long as i am totally in XBOXLIVE from a long time and i havent check the forum in a while. Now i just downloaded again NFS underground 2 and i cannot find the nitro button using the keyboard. (THis question is for my office collegaue who is playing this right now) Any help is greatly appreciated, i checked the faqs ,youtube everything and they had controls for consoles not for PC. Many thanks in advance.

no prob ,he already found out, its ALT button, thanks anyway.