Answer:
800
Step-by-step explanation:
d=2r=2·400=800
I don't know what your choices are, but I did the questions for you.
R=D/2, R=12, R=radius,
SA= 4 times 3.14 12 times 12, so,
SA=1809.557368, if you round it to two decimal places, it'll be,
1809.56, so the answer is 1809.56in. squared.
The way to get the equation for the radius (r) is to get r by itself. So divide each side by 4pi
500/4pi=r^2
Now take the square root of each side to get the equation of r.
sqrt(500/4pi)=r
5ft (i’m just typing because i need more characters)
