Respuesta :

250$ would be the one time expense while 5$ is dependent upon the number of people who read during the summer. so it would be f(x)=250+5x
The answer would be f(x) = 5x + 250.
The problem says "$5 each book" . Meaning for every book, $5 is donated while already having $250 donated to the library. I hope this helps love! :)