A manufacturer has two sites, A and B, at which it can produce a product, and because of certain conditions, site A must produce three times as many units as site B. The total cost of producing the units is given by the function C(x, y)=0.5x-100x - 660y+130000 where a represents the number of units produced at site A and y represents the number of units produced at site B. Round all answers to 2 decimal places. How many units should be produced at each site to minimize the cost? units at site A and What is the minimal cost? $ What's the value of the Lagrange multiplier? at site B