Heyy i would really appriciate some hints or help for this question ( Attachment)

Do I have the right idea for this, please let me know

(PvQ) ==> R (is the same as saying) ~R ==> ~P ^ ~Q (De Morgan's Theorem)

(P==>R)^(Q==R) (is the same as saying (~R==>~P)^(~R==>~Q)

~R ==>~P ^ ~Q is the same as saying (~R==>~P)^(~R==>~Q)

Any help is much appreciated

Or would i make a proof table and say " refering to the proof table.."?

Thanks