• # question_answer Find the total surface area of a cone, it its slant height is 9 m and the radius of its base is 12 m. A)  562 ${{m}^{2}}$                  B)  792 ${{m}^{2}}$  C)  692 ${{m}^{2}}$                  D)  600 ${{m}^{2}}$

(b): $TSA=\pi rl+\pi {{r}^{2}}$ $\pi r+\pi {{r}^{2}}$ $=\frac{22}{7}\left[ 12\times 9+{{12}^{2}} \right]$ $=\frac{22\times 12}{7}\times 21=22\times 12\times 3=792.$