Marie Johnston Is a Manager at a Cell Phone Store

Marie Johnston is a manager at a cell phone store and is making hiring decisions. The number of cell phones her store sells per day depends on the number of workers she hires, as shown in the accompanying table. She sells each cell phone for $300. Assuming that workers are paid $20 per hour and work eight hours, how many employees should Marie hire? What will be the total revenue of her store per day?
$$\begin{array} { | c | c | } \hline \begin{array} { c } \text { Number of } \\\text { workers }\end{array} & \begin{array} { c } \text { Units sold (per } \\\text { day) }\end{array} \\\hline 0 & 8 \\\hline 1 & 13 \\\hline 2 & 17 \\\hline 3 & 20 \\\hline 4 & 22 \\\hline 5 & 23 \\\hline 6 & 23 \\\hline\end{array}$$