Answer:
r = 5 miles
Step-by-step explanation:
[tex]Radius (r) = ?\\Volume = 392.5\\Height (h) = 15\\ V = \frac{1}{3}*pi*r^{2} *h\\392.5= \frac{1}{3} * 3.14 *r^{2} *15\\392.5 * 3 = 1* 3.14 * r^{2} *15\\1,177.5 = 47.1r^{2} \\Divide - both - sides - of -the - equation by 47.1\\r^{2} = 25\\Square -root-both-side-to-eliminate-the-square\\\sqrt{r}^{2} =\sqrt{25} \\r = 5\\r =5 miles[/tex]
