Calculate the margin of error and construct the confidence interval for the population mean using the Student's t-distribution (you may assume the population data is normally distributed).

T-Distribution Table

a. x=85.5,n=66,s=10, 80% confidence

E=

Round to two decimal places if necessary

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Round to two decimal places if necessary

b. x=33.4,n=42,s=16.4, 95% confidence

E=

Round to two decimal places if necessary

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Round to two decimal places if necessary