Find the error in the statistics language in each of the following statements about z, t, or F distributions or their related tests. Explain why it is incorrect and provide the correct word.

a. The professor reported the mean and standard error for the final exam in the statistics class.

b. Before we can calculate a t statistic, we must know the population mean and the population standard deviation.

c. The researcher calculated the parameters for her three samples so that she could calculate an F statistic and conduct an ANOVA.

d. For her honors project, Evelyn calculated a z statistic so that she could compare the mean video game scores of a sample of students who had ingested caffeine with a sample of students who had not ingested caffeine.