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QUESTION 18 A sales manager for an automobile parts retail store wanted to estimate the commission that could be expected from the following data. 2,200 2,500 2,400 1,600 1,500 2,000 2,100 2,300 The manager wanted to be 90% confident that the true mean was found CC = ? QUESTION 19 A sales manager for an automobile parts retail store wanted to estimate the commission that could be expected from the following data. 2.200 2,500 2.400 1,600 1,500 2,000 2.100 2.300 The manager wanted to be 90% confident that the true mean was found a =? QUESTION 20 A sales manager for an automobile parts retail store wanted to estimate the commission that could be expected from the following data. 2.200 2.500 2.400 1,600 1.500 2.000 2.100 2,300 The manager wanted to be 90% confident that the true mean was found Lower Confidence Limit =