how do I figure the sd

re: 22. Part 3 of 7 Points: 0.6 Assume that the differences are normally distributed. Complete parts (a) through (d) below. Observation CO CO X 48.1 45.3 47.5 45.5 49.1 45.0 44.9 44.2 52.4 46.1 49.4 50.9 51.6 46.2 47.3 46.7 . . .. . (a) Determine dj = X; - Y, for each pair of data. CO Observation LO N - 4.3 - 0.8 - 1.9 - 5.4 - 2.5 - 1.2 -2.4 -2.5 (Type integers or decimals.) (b) Compute d and Sd. d = - 2.625 (Round to three decimal places as needed.) (Round to three decimal places as needed. ) S =