How do you solve the last two problems?

The entire list must be recalled in order for the response to be correct. Across all students (n = 8387) who completed this lab, the mean memory span for digits was 6.86 with a standard deviation across students of 1.6. For the word lists, the mean memory span was 4.42 with a standard deviation across students of 1.26. Trial Type of stimulus List length Response Digits 3.0 Incorrect 2 Words 3.0 Correct Digits 2.0 Correct Digits 3.0 Correct Words 4.0 Correct 6 Digits 4.0 Correct Digits 5.0 Correct Words 5.0 Incorrect Words 40 Correct Words 5.0 Incorrect Digits 6.0 Incorrect Words 40 Correct Digits 5.0 Correct Words 5.0 Incorrect Words 40 Incorrect Digits 6.0 Correct Digits 7.0 Correct Digits 8.0 Incorrect Words 3.0 Correct Words 40 Correct Use the trial-by-trial data to answer these questions. Question Answer Status Memory span for digits: (Your answer must exactly equal the correct value.) Check answer Hint Correct Memory span for words: 4 (Your answer must exactly equal the correct value.) Check answer Hint Correct z-score for the memory span for digits: (The difference between your answer and the correct value must be less than 0.01. Check answer |Hint |Incorrect z-score for the memory span for words: (The difference between your answer and the correct value must be less than 0.01.) Check answer | |Hint Incorrect Hint: Subtract the mean for words across all students and then divide by the standard deviation