9000120305

The side of a regular hexagonal prism $ABCDEF{A}^{\prime }{B}^{\prime }{C}^{\prime }{D}^{\prime }{E}^{\prime }{F}^{\prime }$ shown in the picture is $a=3\mathrm{cm}$ and the height is $v=8\mathrm{cm}$. Find the angle between the diagonal $A{D}^{\prime }$ and the base plane $ABC$ (round your result to the nearest degree).