I need help with my stats 18 hw question please .

For the Data presented below; what is the Person Mean for Person 3? Behavior Sub (X - M) (X-M)-2 Cognitive Mean (X - M) (X-M) -2 Therapy Therapy People 1 83 4 16 73 2 4 78.00 2 85 6 36 75 4 16 80.00 3 89 10 100 77 16 36 A 77 -2 4 71 O 74.00 75 -4 16 4 UT 69 -2 72.00 6 73 -6 36 67 4 16 70.00 7 71 64 65 6 36 68.00 Mean Mean Grand BT CT MEAN MEAN 79 71 SS 272 112 SS SS BT CT