Question 1193811
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Hint:
D v A
A v D
~~A v D
~A ⊃ D
I used the material implication rule on the fourth step shown above.


Another hint: 
You'll use the hypothetical syllogism rule exactly twice.
Think of it like a chain of dominos. One statement leads to another which points to another. You'll then use the material implication rule one final time.
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