Two $2\mathrm{.}2-$cmcm$-$diameter$-$disks spaced $1\mathrm{.}8$ mmmm apart form a parallel$-$plate capacitor. The electric field between the disks is $4\mathrm{.}9105$ V$/$mV$/$m $.$

What is the voltage across the capacitor?

How much charge is on each disk?

An electron is launched from the negative plate. It strikes the positive plate at a speed of $2\mathrm{.}4107$ m$/$sm$/$s $.$ What was the electron's speed as it left the negative plate?