Use either IP or CP (or both) and the eighteen rules of inference to derive the conclusions of the following symbolized arguments. You may not use the Direct Method. (15) Find: G ~1 1. FVG 2. H.(IF) 3. HD F (17) Find: C> (E > F) 1. C> (Dv ~E) 2. E (DF) (16) Find: S 1. (E v R) 2. (DVG) > S 3. Ev G (CD) (18) Find: G 1. 1 > F 2. G> (HI) 3. ~(~HvF)