$A$ hemispherical depression is cut out from one face of a cubical wooden block such that the diameter $l$ of the hemisphere is equal to the edge of the cube. Determine the surface area of the remaining solid. $\left[\text{Use } \pi=\frac{22}{7}\right]$

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(N/A) Diameter of hemisphere $=$ Edge of cube $= l$
Radius of hemisphere $r = \frac{l}{2}$
Total surface area of the remaining solid $=$ Total surface area of the cube $+$ Curved surface area of the hemisphere $-$ Area of the circular base of the hemisphere
$= 6(\text{Edge})^2 + 2\pi r^2 - \pi r^2$
$= 6l^2 + \pi r^2$
Substituting $r = \frac{l}{2}$:
$= 6l^2 + \pi \left(\frac{l}{2}\right)^2$
$= 6l^2 + \frac{\pi l^2}{4}$
$= \frac{24l^2 + \pi l^2}{4}$
$= \frac{l^2}{4}(24 + \pi) \text{ unit}^2$

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