Answer
$I = 1.2\times 10^{-2}~A$
Work Step by Step
We can write an expression for the drift speed:
$v_d = \frac{I}{n~q~A} = \frac{I}{n~q~\pi~r^2}$
$I$ is the current
$n$ is the number of electrons per unit of volume
$q$ is the charge of one electron
$A$ is the cross-sectional area
$r$ is the cross-sectional radius
We can find the current $I$:
$v_d = \frac{I}{n~q~\pi~r^2}$
$I = v_d~n~q~\pi~r^2$
$I = (6.5\times 10^{-6}~m/s)(5.90\times 10^{28}~m^{-3})(1.6\times 10^{-19}~C)~(\pi)~(2.5\times 10^{-4}~m)^2$
$I = 1.2\times 10^{-2}~A$
