A company produces two models of calculators at two different plants. In one day Plant A can produce 140 of Model 1 and 35 of Model 2. In one day Plant B can produce 60 of Model 1
and 90 of Model 2. If the company needs to produce at least 460 Model 1 and 340 of Model 2,
find the minimum cost. Assume it costs $1200 per day to operate Plant A and $900 per day for
Plant B.