Question

What is the total surface area of a hemisphere if it's radius is $7cm$?

• A. $264c{m}^2$
• B. $206c{m}^2$
• C. $462c{m}^2$
• D. $642c{m}^2$

Answer 1

Answer: (C)

$462c{m}^2$

Given,

the radius of the hemisphere is $7$ cm.

Then the total surface area of the hemisphere $=3\pi r^2$

$=3\times \frac{22}{7}\times 7^{2}c{m}^2$

$=22\times 21c{m}^2$

$=462$ $c{m}^2$

Hence, the total surface area of the hemisphere is $462$ $c{m}^2$