7.88 A field trial.

The tomato experts who carried out the field trial described in Exercise 7.39 (page 378) suspect that the relative lack of significance there is due to low power. They would like to be able to detect a mean difference in yields of 0.3 pound per plant at the 0.05 significance level. Based on the previous study, use 0.51 as an estimate of both the population and the value of in future samples.