Question 1141036
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1. H ⊃ (B ⊃ ∼M)
2. T ⊃ (H • M)            / T ⊃ ∼B

3. T ⊃ H                   2, simplification
4. T ⊃ (M • H)             2, commutation
5. T ⊃ M                   4, simplification 
6. T ⊃ (B ⊃ ∼M)           3,1, hypothetical syllogism 
7. T ⊃ [(B ⊃ ∼M) • M]     6,5, composition
8. T ⊃ [(B ⊃ ∼M) • ∼∼M]  7, double negation
9. T ⊃ ∼B                 8, modus tollens 

Edwin</pre>