Update index.html

Author: Gmac4247

index.html

@@ -4021,7 +4021,7 @@ <h4 itemprop="description">Subtracting the missing tip from a theoretical full c
 <label itemprop="measuredProperty" for="frustum-cone-height">Height:</label>
 <input id="frustum-cone-height" type="number" value="1" step="any">
 <br><br>
-<p itemprop="measuredProperty" id="frustum-cone-volume"></p>
+<p itemprop="measuredProperty" id="frustum-cone-volume">Frustum cone volume</p>
 </div>
 </div>
 <script type="module" async>