A camera company makes two models of cameras A and B. Model A takes one hour to assemble and one tenth of an hour to test. Model B takes one and half hours to assemble and half an hour to test. Production facilities are such that 32,000 hours per month are available for assembly, while 6,000 hours per month are available for testing. The profit of model A is $60 and for model B is $100. Find the maximum profit obtainable, and describe how many units of each model should be produced per month.