Answer:
D) 70 ft
Step-by-step explanation:
1 inch = 20 feet
3 1/2 inches= 20 feet*3 1/2 inches
= 70 ft
To change a decimal to a fraction, we simply "use as many zeros as there are decimals and lose the dot".
say in this case, 0.8 has 1 decimal, so we'll use one zero at the bottom,
Volume of a sphere = 4/3 πr³
4/3 * 3.14 * r³ = 4000
4.19 * r³ = 4000
r³ = 4000 / 4.19
r = ∛1058
r = 10.19
Now, surface area = 4πr² = 4 * 3.14 * (10.19)²
S.A. = 12.56 * 104
S.A. = 1307
In short, Your Answer would be Option D) 1307 m²
Hope this helps!