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 139 rst 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 identied was 34.12 with a standard deviation of 23.43. Construct a 99% interval for the mean number of letter sounds identied in one minute. Round the answers to two decimal places. A 99% condence interval for the mean number of letter sounds identied in one minute is E] <..>