From a solid circular cylinder with …

Let V be the volume of the remaining solid and S be the whole surface area.
Then,

V = Volume of the cylinder - Volume of the cone.
{tex} \Rightarrow V = \left\{ \pi \times 6 ^ { 2 } \times 10 - \frac { 1 } { 3 } \times \pi \times 6 ^ { 2 } \times 10 \right\} \mathrm { cm } ^ { 3 } = ( 360 \pi - 120 \pi ) \mathrm { cm } ^ { 3 } = 240 \pi \mathrm { cm } ^ { 3 }{/tex}
Slant height of the cone = OC = {tex}\sqrt { O O ^ { \prime 2 } + O ^ { \prime } C ^ { 2 } } = \sqrt { 10 ^ { 2 } + 6 ^ { 2 } } = \sqrt { 136 } \mathrm { cm } = 2 \sqrt { 34 } \mathrm { cm }{/tex}
and, S = Curved surface area of the cylinder + Area of the base of the cylinder + Curved surface area of cone
{tex}S = \left\{ 2 \pi \times 6 \times 10 + \pi \times 6 ^ { 2 } + \pi \times 6 \times 2 \sqrt { 34 } \right\} \mathrm { cm } ^ { 2 } = ( 156 + 12 \sqrt { 34 } ) \pi \mathrm { cm } ^ { 2 }{/tex}