Question 1156254
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1. (A v B) ⊃ T		
2. Z ⊃ (A v B)		
3. T ⊃ W			
4. ~W		/∴~Z

5. ~T           3,4,  Modus Tollens
6. ~(A v B)     1,5,  Modus Tollens
7. ~Z           2,6,  Modus Tollens.

Edwin</pre>