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The Cook County Lumber Co. has three sawmills that produce boards of different lengths. The following table is a joint frequency distribution based on a random sample of 1,000 boards selected from the lumber inventory. Board Length Sawmill 8ft 10ft 12ft 14ft A 140 100 80 14 B 250 20 100 50 160 50 16 20 Based on these data, if a board is selected that is 12 feet long, the probability that it was made at sawmill A is: 0.08 0.41 0.24 0.20