Question 996120
<table border=1><tr><th>Number</th><th>Statement</th><th>Lines Used</th><th>Reason</th></tr><tr><td>1</td><td>~S --&gt; O</td><td></td><td></td></tr><tr><td>2</td><td>O --&gt; S</td><td></td><td></td></tr><tr><td>:.</td><td>S</td><td></td><td></td></tr><tr><td>3</td><td>~S --&gt; S</td><td>1,2</td><td>HS</td></tr><tr><td>4</td><td>~~S v S</td><td>3</td><td>MI</td></tr><tr><td>5</td><td>S v S</td><td>4</td><td>DN</td></tr><tr><td>6</td><td>S</td><td>5</td><td>Taut</td></tr></table>

Abbreviations/Acronyms Used:

DN = Double Negation
HS = Hypothetical Syllogism
MI = Material Implication
Taut = Tautology