Arnold Is the Chief Executive Officer of Beta Corporation

Arnold is the chief executive officer of Beta Corporation.Arnold's re?sponsibilities include decisions on product development,marketing,and other significant business directions.Arnold is subject to the approval and oversight of Beta's board of directors.Carol is a Beta manager whose duties include the firm's day-to-day hiring,firing,purchasing,and sell?ing.Dave is a Beta salesperson,whose daily activities are con?trolled by Carol.Erin writes technical manuals for Beta products ac?cording to Arnold's instructions and subject to Beta's control,but has no dealings with Beta custom?ers or sup?pliers.Fred edits the manuals on a contract-per-manual basis and is not otherwise subject to Beta's control.Who is a principal? Who is an agent? Who is an employee? Who is an independent contractor?