The Alibi Restaurant is normally open for business until $8$ : $00$ ?P $.$ M $.$ ?Recently, business has been getting better during the time period just before closing, and the manager is attempting to determine the viability of remaining open until $9$ : $00$ ?P $.$ M $.$ ?She estimates her additional costs for the extra hour as follows:

EXCEL EXERCISES

$517$

$\backslash$ table $[[$ Labor $,$ $ $75$