The average number of cavities that thirty-year-old Americans have had in their lifetimes is 9. Do twenty-year-old have fewer cavities? The data show the results of a survey of 16 twenty-year-old who were asked how many cavities they have had. Assume that the distribution of the population is normal. 11, 8, 5, 6, 10, 9, 6, 9, 11, 9, 6, 10, 11, 7, 6, 11 What can be concluded at the a = 0.01 level of significance? Write hypothesis, give test stat and p-value. Write conclusions about HO and claim.