When accelerated along a straight line at $2\mathrm{.}8$ x$1015$ m$/$s$2$ in a machine, an electron $($mass m$=9\mathrm{.}1$ x $10-31$ kg$)$ has an initial speed of $1\mathrm{.}4$x$107$ m$/$s and travels $5\mathrm{.}8$ cm$.$ Find $($a$)$ the final speed of the electron and $($b$)$ the increase in its kinetic energy.