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@@ -238,7 +238,7 @@ Un poliedro si dice regolare quando le sue facce sono poligoni regolari congruen
 I poliedri regolari o solidi platonici sono 5: tetraedro, esaedro o cubo, ottaedro, dodecaedro e icosaedro.
 
 |  poliedro                                       | facce | vertici | spigoli | superficie                           | volume                         |
-| :---------------------------------------------: | :---: | :-----: | :-----: | :----------------------------------: | :----------------------------: |
+|:-----------------------------------------------:|:-----:|:-------:|:-------:|:------------------------------------:|:------------------------------:|
 | ![tetraedro](images/tetraedro.jpg) tetraedro    |   4   |    4    |    6    | $s^2 \sqrt{3}$                       | $\frac{1}{12}s^3\sqrt{2}$      |
 | ![esaedro](images/esaedro.jpg) esaedro          |   6   |    8    |    12   | $6s^2$                               | $s^3$                          |
 | ![ottaedro](images/ottaedro.png) ottaedro       |   8   |    6    |    12   | $2s^2 \sqrt{3}$                      | $\frac{1}{3}s^3\sqrt{2}$       |