Hello Ameet,
'
Critical permission can be defined in SAP GRC for that you need to create a function id, which should only consists permission.
Regarding request Cancellation.
well i have cancelled the request,which i have already mentioned and you are asking whether i am sure about it or not. THEN I AM SURE I HAVE CANCELLED THE REQUEST.
and Arun suggestion is about how to cancel request, which i have already said i have cancelled..
Seems you both responding without reading the content properly.
Prasant