Suppose Dr Savage would like to make a new economic textbook, and given his understanding of economics he estimates the long run total cost of writ- ing to be LTC = 20,000Q 200Q^2 + Q^3 and his long-run marginal cost as LMC = 20,000400Q+3Q^2, where (Q) is measured as thousands of words.

• (a) Calculate Dr Savage's long-run average cost of writing by dividing the total cost by Q.
• (b) Calculate the quantity where LAC is at a minimum, using the relation- ship between LMC and LAC.
• (c) What is the lowest possible average cost at which Dr Savage can write?
• (d) Calculate the ranges over which Dr Savage experience economies of scale and diseconomies of scale.