Answer
$C = 8.3\times 10^{-18}~F$
Work Step by Step
We can find the required capacitance:
$f = \frac{1}{2\pi~\sqrt{LC}}$
$f^2 = \frac{1}{4\pi^2~LC}$
$C = \frac{1}{4\pi^2~L~f^2}$
$C = \frac{1}{(4\pi^2)~(15\times 10^{-3}~H)~(450\times 10^6~Hz)^2}$
$C = 8.3\times 10^{-18}~F$
