A Mojave Desert, CA solar$-$based power$-$generating station $($aka "solar farm"$)$ receiving an average daily insolation of $8\mathrm{.}9$ kWH$/$m$2$ uses photovoltaic $($PV$)$ panels possessing a time$-$average operation efficiency of $19\%.$ This Thesize of each panel is $3$m x $1$m$.$

$($a$)$ What is the required area for a solar farm to provide the electrical needs for the State of California?

$($b$)$ What is the annual savings in CO$2$ emissions $($kilogram mass basis$)$ if the all of the CO$2-$producing sources are removed from the California electric power portfolio and replaced by the solar farm?