You are curious to know the average transfer size of Venmo transactions. With the help of your uncle that works for Venmo, you collect anonymous data on 33 random Venmo transactions. You find a sample mean of $51 and a sample standard deviation of $15.

a) Define the parameter of interest.

b) Find a 80% confidence interval for the parameter defined in part a). (Use the provided table, not the calculator to find the appropriate critical value. Indicate the correct degrees of freedom). You do not need to verify assumptions.

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c) interpret the confidence interval computed in part b).

d) Your uncle thinks that the average transfer size of Venmo transactions is $52. If you were to conduct a hypothesis test to test if he is right or wrong, would you reject his claim with significance level .20?