Sound it out: Phonics is an instructional method in which children are taught to connect sounds with letters or groups of letters. A sample of 135 first-graders who were learning English were asked to identify as many letter sounds as possible in a period of one minute. The average number of letter sounds identified was 34.04 with a standard deviation of 23.62. Part: 0 / 2 Part 1 of 2 (a) Construct an 80% confidence interval for the mean number of letter sounds identified in one minute. Round the answers to at least two decimal places. An 80% confidence interval for the mean number of letter sounds identified in one minute is X Part: 1 / 2 Part 2 of 2 (b) If a 90 %% confidence interval were constructed with these data, would it be wider or narrower than the interval constructed in Part (a)? The confidence interval would be (Choose one)