Blue light $($l $=460$ nm$)$ is incident on a piece of potassium $($f $=2\mathrm{.}20$ eV$).$ What is the maximum kinetic energy of the ejected photoelectrons? $($h $=6\mathrm{.}6310-34$ J$$s$,$ c $=3\mathrm{.}00108$ m$/$s$,1$ eV $=1\mathrm{.}6010-19$ J$,$ and $1$ nm $=10-9$ m$)$

Question $10$ options:

$1)$

$1\mathrm{.}0$ eV

$2)$

$0\mathrm{.}50$ eV

$3)$

$0\mathrm{.}25$ eV

$4)$

$4\mathrm{.}9$ eV

$5)$

$6\mathrm{.}2$ eV