A researcher collects data on two independent samples. The first group consists of 20 human subjects, has a sample mean of 4.21, and a standard deviation of 1.4. The second group consists of 20 subjects, has a sample mean of 3.15, and a standard deviation of 1.8. Test the null hypothesis that there is no difference between the population means of the two groups at the .01 level of significance. Indicate
a) The observed value of the test statistic,
b) The critical value(s)
c) Whether you reject or fail to reject the null hypothesis.