Total surface area of a cuboid measuring $15\,cm \times 12\,cm \times 10\,cm$ is $\ldots \ldots \ldots \,cm^{2}$.

In a right circular cone,the cross-section made by a plane parallel to the base is a

Three metallic solid cubes whose edges are $3 \, cm$,$4 \, cm$,and $5 \, cm$ are melted and formed into a single cube. Find the edge of the cube so formed (in $cm$).

The volume of a frustum of a cone is equal to $\ldots \ldots \ldots . .$

$16$ glass spheres,each of radius $2 \,cm$,are packed into a cuboidal box of internal dimensions $16 \,cm \times 8 \,cm \times 8 \,cm$. The box is then filled with water. Find the volume of water filled in the box (in $cm^3$).

Write 'True' or 'False' and justify your answer:
The curved surface area of a frustum of a cone is $\pi l(r_{1}+r_{2})$,where $l = \sqrt{h^{2}+(r_{1}+r_{2})^{2}}$,$r_{1}$ and $r_{2}$ are the radii of the two ends of the frustum,and $h$ is the vertical height.