31. An Austin Mini and a Nissan Maxima leave an intersection in Kingston at the same time. The Austin Mini, driven by J ackie, travels south at 80 knu'h, and the Maxima, driven by Josh, travels east at 90 kmr'h. At what rate is the distance between the two cars changing 30 minutes later, assuming the}r can continue to travel at the given initial speeds? 32. Priscilla and Graham want to build a to}.{ \"George in the Box". They have a square piece of cardboard that is 12EI cm wide. Describe how the}r can build an open top box with the cardboard and determine the dimensions of the box that will have the largest volume