17. A developmental psychologist is examining the development of language skills from age 2 to age 5.

Four different groups of children are obtained, one for each age, with n 15 children in each group. Each child is given a language skills assessment test. The resulting data were analyzed with an ANOVA to test for mean differences between age groups. The results of the ANOVA are presented in the following table.

Fill in all missing values.

Source SS df MS Between treatments 81 F Within treatments Total 249