Performance scores on a motor skills task form a normal distribution with μ = 20 and σ = 4. A psychologist is using this task to determine the extent to which increased self-awareness affects performance. The prediction for this experiment is that increased self-awareness will reduce a subject's concentration and result in lower performance scores. A sample of N = 16 subjects is obtained, and each subject is tested on the motor skills task while seated in front of a large mirror. The purpose of the mirror is to make the subjects more self-aware. The mean score for this sample is = 15.5. U a one-tailed z test with α = .05 to test the psychologist's prediction (include all elements as detailed in z-Test Handout).