Question 111
The base face of an upright prism is a deltoid, which has a shorter diagonal of length $e$. The internal angles of the deltoid with the peaks in the places of the longer diagonal measure $90^{\circ}$ and $60^{\circ}$. The height of the prism is equal to the longer diagonal of the deltoid. Express the free prism notino with $e$. The result should be accurate.