A cognitive psychologist interested in the development of thinking skills in children compared samples of three-year-old and five-year-old children on how accurately they categorized a series of concepts. The results were as follows. Three Year Olds: N = 11 M = 22 S2 = 6.5 Five Year Olds: N = 19 M = 27 S2 = 4.5 If the standard deviation of the distribution of the difference between means is 0.86, what is the t score