Problem

Question 9
10 pts
One of the values $\mathrm{r}$ (radius), $\mathrm{d}$ (diameter), $\mathrm{V}$ (volume), or $\mathrm{S}$ (surface area) is given for a particular sphere. Find the indicated value. Leave $\pi$ in your answer.
\[
\mathrm{V}=\frac{1372}{3} \pi \mathrm{ft}^{3} ; \mathrm{S}=?
\]
$14 \pi \mathrm{ft}^{2}$
$196 \mathrm{ft}^{2}$
$196 \pi \mathrm{ft}^{2}$
$\frac{196}{3} \pi \mathrm{ft}^{2}$

Answer

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Answer

So, the surface area of the sphere is \(\boxed{196 \pi}\) square feet.

Steps

Step 1 :Given that the volume of the sphere is \(\frac{1372}{3} \pi \) cubic feet.

Step 2 :The volume of a sphere is given by the formula \(V = \frac{4}{3} \pi r^3\).

Step 3 :Setting the given volume equal to the formula, we get \(\frac{1372}{3} \pi = \frac{4}{3} \pi r^3\).

Step 4 :Solving for \(r^3\), we divide both sides by \(\frac{4}{3} \pi\), yielding \(r^3 = \frac{1372}{4}\) cubic feet.

Step 5 :Simplifying, we find that \(r^3 = 343\) cubic feet.

Step 6 :Taking the cube root of both sides, we find that \(r = \sqrt[3]{343}\) feet.

Step 7 :Simplifying, we find that \(r = 7\) feet.

Step 8 :The surface area of a sphere is given by the formula \(S = 4 \pi r^2\).

Step 9 :Substituting \(r = 7\) feet into the formula, we get \(S = 4 \pi (7)^2\) square feet.

Step 10 :Simplifying, we find that \(S = 4 \pi \times 49\) square feet.

Step 11 :Simplifying further, we find that \(S = 196 \pi\) square feet.

Step 12 :So, the surface area of the sphere is \(\boxed{196 \pi}\) square feet.

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