Marben packaging makes open boxes(no Top) out of cardboard squares whose sides are 6 ft. long. What is the maximum volume they can obtain from the cardboard

Defferentiables Two highways intersect at right angles. Car A on one highway is 0.5 kilometer from the intersection and is moving toward it at 96 kilometers per hour, while car B on the other highway is 1 kilometer from the intersection and is moving away from it at 88 kilometers per hour. At what rate is the distance between the two cars changing at the instant.