A questionnaire was designed to compare the level of students' familiarity with two types of product. For a random sample of 120 students, the mean familiarity level with burglar alarms was found to be 3.355, and the sample standard deviation was 2.03. In an independent random sample of 100 students, the mean familiarity level for television was 9.5, and the sample standard deviation was 2.1. Assuming that the two population distributions are normal and have the same variance, test the null hypothesis that the population means are equal.