What is this monopolistic firm's total profit? Total Marginal Marginal Quantity Price Revenue Revenue Total cost Cost Average Cost 10 $23 $230 $340 $34 20 $20 $400 $17 $400 $6 $20 30 $18 $540 $14 $480 $8 $16 40 $16 $640 $10 $580 $10 $14.50 50 $14 $700 $6 $700 $12 $14 60 $12 $720 $2 $840 $14 $14 70 $10 $700 -$2 $1,020 $18 $14.57 80 $8 $640 -$6 $1,280 $26 $16 Select an answer and submit. For keyboard navigation, use the up/down arrow keys to select an answer. a $60 b $0 C $720 d $840