20. A set of sample scores from an experiment has an N = 30 and an x̅ obt = 19. a. Can we reject the null hypothesis that the sample is a random sample from a normal population with µ= 22 and σ = 8? Use α .01 1 tail . Assume the sample mean is in the correct direction. b. What is the power of the experiment to detect a real effect such that µ= real = 20? c. What is the power to detect a µ= real = 20 if N is increased to 100?