You have been asked to help the local commercial radio station prepare its business plan for the upcoming year. The radio station operates for 18 hours a day ( 6 a.m. to midnight) seven days a week, all year. It broadcasts on average 15 minutes of on-air advertising per hour. To sell the advertising time, the station uses commissioned sales staff who are paid a base salary plus commission that varies according to the volume of sales. The station manager asks you to calculate how many hours of advertising i would need to sell in order to break even. (a) Select the fixed costs and the variable costs. (a) Select the fixed costs and the variable costs