Cost Assignment The sales staff of Central Media (a locally owned radio and cable television station) consists of two salespeople, Derek and Lawanna. During March, the following salaries and commissions were paid: Salaries Commissions Derek Lawanna $20,300 $32,700 9,000 1,300 Derek spends 100% of his time selling advertising. Lawanna spends two-thirds of her time selling advertising and the remaining one-third on administrative work. Commissions are paid only on sales.