Question

If the radius of the base of a right circular cone is $2cm$ and its slant height is $3.5cm$, then its curved surface area is:

• A. $44c{m}^2$
• B. $77c{m}^2$
• C. $22c{m}^2$
• D. $154c{m}^2$

Answer 1

Answer: (C)

Given the radius of the base of a right circular cone $\left(r\right)=2$ cm, and its slant height $\left(l\right)=3.5$ cm.

Then, its curved surface area $=\pi rl=\frac{22}{7}\times 2\times 3.5=22$ cm${}^2$.

Therefore, option $C$ is correct.