User productivity systems $\_\_\_\_.$provide job$-$related information to users at all levels of a companysimulate human reasoning by combining a knowledge base and inference rules that determine how the knowledge is appliedprocess data generated by day$-$to$-$day business operationsinclude e$-$mail, voice mail, fax, video and Web conferencing, word processing, automated calendars, database management, spreadsheets, desktop publishing, presentation graphics, company intranets, and integrated mobile computing systems