Question

If a hemisphere has radius __ cm, then total surface area of the hemisphere is 9.42 ${cm}^2$.

(Take $\pi$ = 3.14)

Answer 1

Total surface area of a hemisphere is given as 3 $\pi$ $r^2$

$\Rightarrow$ 3 $\pi$ $r^2$ = 9.42

$\Rightarrow$ $r^2$ = 1 ${cm}^2$

$\Rightarrow$ r = 1 cm