Answer
$C = 8.1\times 10^{-8}~F$
Work Step by Step
We can find the capacitance $C$:
$I_C = V_C~\omega~C$
$C = \frac{I_C}{V_C~\omega}$
$C = \frac{I_C}{\sqrt{2}~V_{rms}~2\pi~f}$
$C = \frac{65\times 10^{-3}~A}{(\sqrt{2})~(6.0~V)~(2\pi) (15\times 10^3~Hz)}$
$C = 8.1\times 10^{-8}~F$
