APPLICATION: A local outlet store charges $2.00 for a pack of four AA batteries. On an average day, 200 packs are sold. A survey indicates that sales will decrease by 5 packs per day for each $0.10 increase in price.

a. Complete the table above based on the results of the survey.
b. Calculate the first and second differences for the revenue.
c. Let x represent the selling price in dollars, and let y represent the revenue in dollars. Write a function that describes the relationship between the revenue and the selling price.
d. Graph your function and find the maximum revenue. What selling price provides maximum revenue?

2.00 2.10 2.20 2.30 2.40 Selling price (S) Number sold Revenue ($) 200 | 400