Given that the electron effective mass m$*$ e for the GaAs is $0\mathrm{.}067$me$,$ calculate the thermal velocity of the electrons in the conduction band $($CB$).$ The electron drift mobility e depends on the mean free time e between electron scattering events $($between electrons and lattice vibrations$).$ Given e $=$ ee $$m$*$ e $,$ and e $=8500$ cm$2$V$1$ s $1$ for GaAs, calculate e $,$ and hence the mean free path $$ of CB electrons. How many unit cells is $$ if the lattice constant a of GaAs is $0\mathrm{.}565$ nm$?$ Calculate the drift velocity vd $=$ eE of the CB electrons in an applied field E of $104$ V m $1.$ What is your conclusion?