Question

Find the surface area of a sphere of diameter 21cm.​

Answer 1

Answer:

$1386$

Step-by-step explanation:

diameter =21

radius=21/2

surface area =4πr^2

$4 \times \frac{22}{7} \times \frac{21}{2} \times \frac{21}{2}$

$22 \times 21 \times 3$

$462 \times 3$

$1386$