A diffraction grating $($multi slit$)$ with $700$ lines$/$mm is illuminated with light of wavelength $650$ nm$.$ A very wide viewing screen is $2\mathrm{.}00$ m from the grating. a$)$ What is the linear distance between the zero$-$ and first$-$order diffraction maxima?$(1\mathrm{.}02$ m$)$ b$)$ What is the maximum number of bright fringes that could be observed? $(5)$