The following information pertains to the physical inventory of Electronics Unlimited taken at December $31$ :

$\backslash$table$[[,,$Per Unit$],[$Product$,$Units on$,,,],[$Audio equipment:,,,,$],[$Wireless audio receivers,,,,$],[$Touchscreen MP$3$ players,$325,$$$191,$$$180,],[$Audio mixers,$240,195,215,],[$Audio stands,$306,185,169,],[$Video equipment:,$184,77,95,],[$Televisions$,,,,],[5$GB video cards,$460,245,290,],[$Satellite video recorders,$271,163,175,],[$Car equipment:,$192,605,610,],[$GPS navigators,$165,163,137,],[$Double$-$DIN Car Deck with iPod$/$iPhone Control,$150,205,190,],[,$ and Aux Input,,,,$]]$

Required:

Calculate the LCNRV for the:

a$.$ inventory by major group

b$.$ inventory, applied separately to each product.