An alpha particle $)=+2$e$,$m$=(4\mathrm{.}00$u $$travels in a circular path of radius $5\mathrm{.}44$cm $$in a uniform magnetic field with B$=1\mathrm{.}01$T$.$Calculate $($a$)$its speed, $($b$)$its period of revolution, $($c$)$its kinetic energy, and $($d$)$the potential difference through which it would have to be accelerated to achieve this energy.