optimizing cost of a container

A closed rectangular container with a square base is to have a volume of http://edugen.wileyplus.com/edugen/s...=1343834369542 The material for the top and bottom of the container will cost http://edugen.wileyplus.com/edugen/s...=1343834369542 per http://edugen.wileyplus.com/edugen/s...=1343848723493 and the material for the sides will cost http://edugen.wileyplus.com/edugen/s...=1343834369542 per http://edugen.wileyplus.com/edugen/s...=1343848723493 Find the dimensions of the container of least cost.

Length of edge of base= in?

Height= in?