The distribution of X is exponential with an average of 34. Suppose that you form random samples of size 26 from this distribution. Find the following, rounding probabilities to 4 decimals and everything else to 2 decimals. a. The average of X-bar is and the standard deviation of X-bar is For the following, use the average and standard deviation found in part a. b. Find P(X-bar > 42). b. Find P(30 < X-bar < 40). c. 40% of the averages are AT LEAST how much?

Agroup of student volunteers participates in a study designed to assess several behavioral interventions for improving output in a repetitive task. prior to the beginning of the study, all volunteers unknowingly observed, and their output is measured. at the beginning of the study, prior to any intervention, the volunteers perform the same task under the observation of a study administrator, and their overall output increases. which of the following terms describes this phenomenon? a. simpson's paradox b. hawthorne effect are d. novelty effect d. pygmalion effect e. observer-expectancy effect