Many people take ginkgo supplements advertised to improve memory. Are those over the counter supplements effective? A study was conducted where 100 randomly selected adults were given 40 mg of Gingko and 105 randomly selected adults were given a placebo pill. Each group consumed the supplement 3 times/day. At the end of six weeks a test was done of short term memory. The average score for those taking the Gingko pill was 5.8 with a standard deviation of .6. The average score for those taking the placebo pill was 5.5 with a standard deviation of .9. Based on these results, is there evidence that Gingko is effective in improving short term memory. What is the value of the Test Statistic for this hypothesis test? Round Z to the 100ths place.