Find the sum of the lengths of all edges of a rectangle of a parallelepiped, the dimensions of which are 13 cm, 16 cm, 21 cm.

The parallelepiped has 4 identical edges. The sum of the lengths of the edges (S) is 4 * (A + B + C).
In our case, S = 4 * (13 + 16 + 21) = 4 * 50 = 200 cm.

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