The data below refer to the Text Messager study from Field's text. The text messager study examined the effect of unrestricted text messaging compared to none on grammar in 50 primary school children randomized to one or the other condition. Grammar was assessed before and after the intervention. Higher scores represent better grammar test performance, Descriptive data for post intervention grammar scores for the Messager group are given. ## group: Messagers # # vars n mean sd min max range ## 1 1 25 53 16 9 78 69 a. Using the sample descriptive statistics, compute the 95% CI for the mean. b. Interpret this 95% CL c. If you wished to have a more precise estimate of the mean, what should you do? d. If you wanted have greater certainty that your CI contained the population mean, what should you do? e. If the population mean for grammar score among children was 62, what might you conclude from these observations