During its first month of operations, Purrfect Pets purchased 6,900 bags of dog food at a cost of $2 a bag and sold all 6,900 bags of dog food on account with payment terms of 3/10, n/30 for $11 each. A total of 2,900 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. Required: a. Calculate the gross profit for the month. b. Calculate the gross profit percentage for the month