competitive firm 2 quantity (units) total revenue ($) total cost ($) 0 0 30 1 80 50 2 160 80 3 240 120 4 320 170 5 400 230 6 480 300 7 560 380 8 640 470 reference: ref 11-9 (table: competitive firm 2) refer to the table that shows the revenue and cost schedules for a competitive firm. what is the average cost at the profit-maximizing quantity? group of answer choices $80 $58.75