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Question 3: Suppose a manufacturer produces a product, and sells it $6 per unit. 3 a) Write the total revenue (ytr) function. If he sells 20 units, what is the total revenue? b) For the same product, if the fixed cost is $4000 and the variable cost is $ per unit, i) What is the total cost function (Ytc)? ii) What is the total cost of producing 400 items? c) Find the total output (quantity) and the total revenue at the break-even point. d) Draw the total cost and total revenue curves and show the break-even point. e) Find the profit when 900 units are produced. f) Find the loss when 200 items are produced. g) Find the quantity in order to obtain a profit of $2000