Question 1193364
Need the data table.
No, you don't have to pay.
In order to answer the question, we need the variance.
the 95% half-interval is t(0.975, df=9)*s/sqrt(10)
I know the past mean, but I do not know the mean of the 10 values. I know t, but I do not know s, the std dev. of the sample. The mean and sd of the sample of 10 are both needed.