    Bentence 1: After it hasbeen installed, the DOS, :as itis.  called (otice identified, nothing in, comiputeres¢ is ever called by,  its fill- name, a Personal’ Computer’ beoomes, a PC;-a. Disk  Operatitig, System becomes: a DOS. if it’ is “made bya.  comipany called MicroSoft, ‘it is called MS/DOS), performs  céreainefinesions, “thiugh rarely. aiy “that. anyone but’,a  computer specialist.would want, wo perforin,    Bentence ‘a: Nothing in computer sense is called by ss fill    name,    