$.)$

$($A$)$ For each of these three segments, find the current I.

$I_{\text{t}\text{o}\text{p}}=A,I_{\text{m}\text{i}\text{d}}=A,I_{\text{b}\text{o}\text{t}}=$ A$.$

$($B$)$ For each of these three segments, find the current density $J.$

$J_{\text{t}\text{o}\text{p}}={10}^6\frac{A}{m^2},J_{\text{m}\text{i}\text{d}}={10}^6\frac{A}{m^2},J_{\text{b}\text{o}\text{t}}=1\mathrm{.}59{10}^6\frac{A}{m^2}$

$($C$)$ For each of these three segments, find the electric field $E.$

$E_{\text{t}\text{o}\text{p}}=,\frac{V}{m},E_{\text{m}\text{i}\text{d}}=,\frac{V}{m}{E}_{\text{l}\text{o}\text{t}}=,\frac{V}{m}$

$$

$$

$($D$)$ For each of these segments, find the drift velocity $v_d.$

$v_{d,\text{t}\text{o}\text{p}}=,{10}^{-3}\frac{m}{s},v_{d,\text{m}\text{i}\text{d}}=,{10}^{-3}\frac{m}{s},v_{d,\text{b}\text{u}\text{l}}=,{10}^{-3}\frac{m}{s}$