The formula to find the surface area of a sphere is:
[tex]A=4 \pi r^2[/tex]
Let's plug in 7 for [tex]r[/tex].
[tex]A=4 \pi *7^2[/tex]
The area would be:
[tex]A=615.75[/tex]
The answer is just an approximation due to the fact that we are using [tex] \pi [/tex]
Let me know if you have any questions!
Thanks!
-TetraFish