USPS offers the flat-rate shipping option below small box : 5 3/8 by 8 5/8 inches by 1 5/8 inches cost:$ 6.80 medium box: 11 7/8 inches by 3 3/8 inches by 13 5/8 cost : $13.45 large box 12 inches by 12 inches by 5 1/2 cost: $18.75 An artist makes necklaces and packs each necklace in a small jewelry box that is inches by 1 3 /4 by 2 1/4 inches by inch. A department store ordered 270 necklaces. The artist plans to ship the necklaces 3 /4 to the department store using USPS flat-rate shipping boxes. Which flat-rate box should this artist use to minimize his shipping costs?