Surface area = 2(ab + bc + ca). Lower limits: a = 4.5 \\text{ cm}, b = 5.5 \\text{ cm}, c = 2.5 \\text{ cm}. SA = 2(4.5 \\times 5.5 + 5.5 \\times 2.5 + 4.5 \\times 2.5) = 2(24.75 + 13.75 + 11.25) = 94 \\text{ cm}^2. Upper limits: a = 5.5 \\text{ cm}, b = 6.5 \\text{ cm}, c = 3.5 \\text{ cm}. SA = 2(5.5 \\times 6.5 + 6.5 \\times 3.5 + 5.5 \\times 3.5) = 2(35.75 + 22.75 + 19.25) = 141 \\text{ cm}^2.