Vera orders some prints of photos that she uploaded to her computer. she orders 3 of the 5 x 7 prints for $0.89 each, 12 of the 4 x 6 prints for $0.15 each and 1 of the 8 x 10 prints for $2.99. she also orders a photo album for $8.69. vera pays taxes that are 7% of the total purchase price. her shipping charges are based on the following table: vera selects standard shipping and the company bills her credit card $20.78 for the total of the online purchase. determine if vera has been billed correctly for her purchase.