$\frac{1}{3}\pi r^2h \; =\;\frac{4}{3}\pi R^3$;
$r^2h\; =\; 4R^3$
81 x 12 = 4R<sup>3</sup>
$3\sqrt{\frac{81\times 12}{4}}$ = R
R = 6.24 cm
Area of sphere = 4$\pi R^2$
= 4 x 3.142 x 6.24 x 6.24
= 489.4 cm$^2$
johnmulu answered the question on March 8, 2017 at 05:41
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