Question 1140111
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1. G⊃(H⊃K)
2. (H∨∼M)⊃∼K
3. H             / ∼G ∨ ∼H

4.  H∨∼M         3, addition
5.  ~K           2,4 modus ponens
6.  G⊃(~H∨K)     1,  material implication
7. ~G∨(~H∨K)     6.  material implication
8. (~G∨~H)∨K     7.  association
9. K∨(~G∨~H)     8.  commutation
10. ∼G∨∼H        9,5, disjunctive syllogism

Edwin</pre>