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The longer leg of a 30-60-90 trangle is 18

Arandom sample of 45 observations results in a sample mean of 68. the population standard deviation is known to be 23 a. compute the margin of error at a 959% confidence interval. b. compute the 95% confidence interval for the population mean c. compute the 90% confidence interval for the population mean. d. compute the 75% confidence interval for the population mean

Stefan's sculpture is 7/12 foot tall. he attaches it to a base that is 1/3 foot tall. how tall, in feet, is the sculpture with the base?