<PRE><B>Question 1109367</B>
As a weather balloon is inflated, its radius increases at the rate of 4 cm per second. Express the volume of the balloon as a function of time, and determine the volume of the balloon after 4 seconds.
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{{{V = 4pi*r^3/3}}}
dV/dt = 4pi*r^2*dr/dt --- 1st derivative
dV/dt = 16pi*r^2 cc/sec
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If you mean 4 seconds after its volume was zero:
{{{V = 4pi*r^3/3 = 4pi*16^3/3}}}
= 16384*pi/3 cc




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