What is the RMS speed of Helium atoms when the temperature of the Helium gas is $243\mathrm{.}0$ K$?($Possibly useful constants: the atomic mass of Helium is $4\mathrm{.}00$ AMU, the Atomic Mass Unit is: $1$ AMU $=1\mathrm{.}66\backslash$times $10-27$ kg$,$ Boltzmann's constant is: kB $=1\mathrm{.}38\backslash$times $10-23$ J$/$K$.)$

$($in m$/$s$)$