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(*) A rectangular photo frame encloses an area of 800 cm-. The top edge of the frame is constructed out of heavier material than the other three sides. The material for the top edge weighs 200 g/ cm and the other three sides are made from material weighing 100 g/cm. In this question we will calculate the dimensions of the frame that minimize the total weight. y a) Write an expression in terms of x and y for the total weight of the frame. Weight = b) Find a constraint that allows you to express y in terms of x y = a) Write an expression in terms of x and y for the total weight of the frame. Weight = b) Find a constraint that allows you to express y in terms of x EEB y = c) The values of x and y that minimize the total weight are C min = cm FEB ymin = cm