12. A local boutique sells water bottles for a sel pre plus an additional fee for each eller that customers would like engraved on their water bolllo. The pricing for up to 1 engraved lettera la
shown in the table below
w of Letters
0
2
4
Total Cost
18.991
19.34
19.69
20.04
20.39
Write an equation to represent the relationship between the number of letters and the total cost,