Question 980258
<table border=1>
  <tr>
    <th></th>
    <th></th>
    <th></th>
    <th></th>
    <th>Premise</th>
    <th>Premise</th>
    <th>Conclusion</th>
  </tr>
  <tr>
    <th>P</th>
    <th>W</th>
    <th>P &amp; W</th>
    <th>P v W</th>
    <th>P &lt;--&gt; W</th>
    <th>~(P &amp; W)</th>
    <th>~(P v W)</th>
  </tr>
  <tr>
    <td>T</td>
    <td>T</td>
    <td>T</td>
    <td>T</td>
    <td>T</td>
    <td>F</td>
    <td>F</td>
  </tr>
  <tr>
    <td>T</td>
    <td>F</td>
    <td>F</td>
    <td>T</td>
    <td>F</td>
    <td>T</td>
    <td>F</td>
  </tr>
  <tr>
    <td>F</td>
    <td>T</td>
    <td>F</td>
    <td>T</td>
    <td>F</td>
    <td>T</td>
    <td>F</td>
  </tr>
  <tr>
    <td>F</td>
    <td>F</td>
    <td>F</td>
    <td>F</td>
    <td>T</td>
    <td>T</td>
    <td>T</td>
  </tr>
</table>


There is no row that has all true premises with a false conclusion. So this argument is <font color="red">valid</font>. An invalid argument only happens when all premises are true leading to a false conclusion.