Update index.html

Angles

Author: Gmac4247

index.html

@@ -2583,6 +2583,9 @@ <h4>Archimedes and the Illusion of Limits</h4>
       <li>60°</li>
       <li>45°</li>
       <li>30°</li>
+	<li>22.5°</li>
+	<li>15°</li>
+	<li>7.5°</li>
 </ul> 
 <br>
 <p>These arise from:</p>