During its first month of operations, Purrfect Pets purchased 6, 700 bags of dog food at a cost of $7 a bag and sold all 6, 700 bags of dog food on account with payment terms of $ 2/10, net 30 for $11 each. A total of 2, 100 of these bags were sold to customers who paid within the discount period: the other customers paid after the discount period had ended. Sales allowances totaling $220 were granted to customers whose dogs did not like the dog food. a. Calculate the gross profit for the month. b. Calculate the gross profit percentage for the month