The standard deviation A) All of these are correct. B) cannot be negative. C) is based on squared deviations from the mean. D) is in the same units as the mean. acer

Answer is only partly right

I am still confused

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A survey asked, "How important is it to you to buy products that are made in America?" Of the 600 Americans surveyed,450 responded, "It is important." For each of the following levels of confidence, find the sample proportion and the marginof error associated with the poll. (Round the margin of error to one decimal place.) (a) an 85% level of confidencesample proportion _ margin of error ± _ % (b) a 98% level of confidencesample proportion _margin of error ± _ %