Question: A researcher is interested in testing to determine if the mean of population one is different than the mean of population two. The null hypothesis is that there is no difference in the population means (i.e. the difference is zero). The alternative hypothesis is that there is a difference. She randomly selects a sample of 7 items from population one resulting in a mean of 17.3 and a standard deviation of 3.4. She randomly selects a sample of 12 items from population two resulting in a mean of 15.8 and a standard deviation of 2.9. She is using an alpha value of .10 to conduct this test. Assume the populations are normally distributed. The observed t value is:
a) 2.15
b) 0.49
c) 1.02
d) 1.80