$$An electric field is uniform in space but varies with time given by the equation: 

 

$E(t)=[4\mathrm{.}0e-t-2\mathrm{.}0sin(0\mathrm{.}2t)]$

$($a$)$ Find an expression for the velocity of an electron, initially at rest, as a function of time.

$($b$)$ If the electron starts at the origin at $t=0,$ what is the particle's position at $t=3\mathrm{.}0sec?$