Total Cost in a day is

. Profit function is

. And the revenue function is

. In a day, bookstore must sell at least 15 books, because of 6n-90=0, in order to make profit.
THE ANSWER IS THAT A= 1.25
($9.20) 2 = $18.40 ...................
I think its a) 172.50 but im not exactly sure.
Answer:
plug n and r into the equation for the answers.
Step-by-step explanation: