The ubiquitous 12oz aluminum cans used to distribute drinks in this country have a diameter of approximately 2.75 inches and a height of 5.0 inches. Estimate the amount of aluminum that could be saved if the cans were designed with the ratio $d/h=1$, while having the same volume as the standard 12oz can.
Amount of aluminum saved, as a percentage of the amount used to make the optimal cans, equals .

What would be the diameter and height (in inches) of the new and improved cans?
.