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 it would need to sell in order to break even.

$($a$)$ Select the fixed costs and the variable costs.

$$ Rent

$$ Utilities $($heat$,$ light, water$)$

$$ Property and business taxes

$$ Management salaries and benefits

$$ Marketing costs for the station

Sales force base salaries

$$ Costs of production of on$-$air commercial

$$ Advertising sales commission