Question 1179976
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1. O ⊃ (Q • N)
		
2. (N ∨ E)⊃ S	/ O ⊃ S

                 | 3. O         assumption for conditional proof
                 | 4. Q • N     1,3, modus ponens
                 | 5. N • Q     4, commutation
                 | 6. N         5, simplification
                 | 7. N v E     6, addition
                 | 8. S         2,8 modus ponens
9. O ⊃ S          lines 3-8        conditional proof 

Edwin</pre>