A copper wire has a circular cross section with a radius of $4\mathrm{.}75$ mm$.$

$($a$)$ If the wire carries a current of $2\mathrm{.}70$ A$,$ find the drift speed of the electrons in the wire. $($Assume the density of charge carriers $($electrons$)$ in a copper wire is n $=8\mathrm{.}461028$ electrons$/$m$3.)$

m$/$s

$($b$)$ All other things being equal, what happens to the drift speed in wires made of metal having a larger number of conduction electrons per atom than copper? Explain.