Dr. Nick Riviera claims that herbal supplements such as gins…

Dr. Nick Riviera claims that herbal supplements such as ginseng or ginkgo biloba enhance human memory. To test this claim, he selects a sample of n = 144 adults. Each participant takes a ginkgo biloba supplement daily for six weeks. After the six weeks, all participants are given a standardized memory test. Scores on the test are normally distributed with μ = 95 and σ = 18 for the population. The sample of n = 144 adults had a mean score of M = 99.  The effect size (Cohen’s d) would be ____________.