Ma Bell's $9âBillion Captive
Article on Western Elec, which mfrs telephone equipment for Bell System, 1 of series on AT&T and its impact on Amer life and business; co says avg price of equipment rose only 38% between 1950 and 1978 and that avg price of co's equipment stands 18% below that of other phone equipment mfrs; co pres is Donald Procknow; illus (L)