In the Census of Manufactures the cane sugar industry has a four firm concentration ratio of 60 (sum of market share of the largest 4 firms is 60%) and total sales of $2 billion and the beet sugar industry has a four firm concentration ratio of 60 and total sales of $2 billion. Because cane sugar and beet sugar are nearly perfect substitutes in use, it would have been better if the census had computed the HHI on the sugar market that combined both the beet sugar and the cane sugar markets.

a) Compute the maximum possible CR4 for the combined "sugar" industry. b) Compute the minimum possible CR4 for the combined "sugar" industry. Explain how you reached your answers.