difference = 3 ft²
Surface area of box J
= 2( 4.5 × 3 ) + 2( 2 × 3 ) + 2( 4.5 × 2 ) = 27 + 12 + 18 = 57 ft²
Surface area of box F
note that F is a cube with 6 square faces = 6( 3 × 3 ) = 54 ft²
difference = 57 - 54 = 3 ft²
