Shay works each day and earns more money per hour the longer she works. Write a function to represent a starting pay of $20 with an increase each hour by 4%. Determine the range of the amount Shay makes each hour if she can only work a total of 8 hours.
20 ≤ x ≤ 22.51
20 ≤ x ≤ 25.30
20 ≤ x ≤ 26.32
20 ≤ x ≤ 27.37