please help with 6-8

Use the following to answer questions 6-8: ATO Price 30 D, MR 21 20 AVC 12 10 8 . N 7 10 11 12 13 14 15 Quantity 6. In the figure above, what is the profit-maximizing price and output level? A) $8 and 10 units B) $17 and 30 units c) $20 and 13 units D) $30 and 15 units 7. In the figure above, what is the amount of profit the firm carns at the profit- level of output? A) $90 B) $450 C) $9 D) $135 8. In the figure above, what is the firm's short run shutdown price? A) $2 B) $8 C) $20 D) $30