$11\mathrm{.}31)$ An alpha$-$particle $($m $=6\mathrm{.}64$x$1027$ kg$,$ q $=3\mathrm{.}2$x$10-19$ C$)$ travels in a circular path of radius $25$ cm in a uniform magnetic field of magnitude $1\mathrm{.}5$ T$.($a$)$ What is the speed of the particle? $($b$)$ What is the kinetic energy in electron$-$volts