What is the corresponding critical t-value for Type I error rate of a =0.05 ?

Below is the data for a personality questionnaire measuring "Openness to New Experiences". These data were taken from a random sample of 100 undergraduate psychology majors. In the general population, scores on this questionnaire are normally distributed with a mean (p) of 70. You hypothesize that this sample is not representative of the general population. Specifically, you hypothesize that psychology students form a distinct sub-population, with DIFFERENT Openness, relative to the general population. That is, it would be equally interesting to find out they have higher or lower Openness. Conduct a one-sample t-test by answering the following questions. Data: N = 100, xbar (sample mean) = 75.12, S. = 10.17 a. State the null and alternative hypotheses. Null: p = 70 Psychology students have the same openness to new experiences as the general population. Alternative: p # 70 Psychology students' average openness to new experiences (u) does not equal 70 b. Are you going to be using a one- or two-tailed test? Explain the reason for your choice. I will use a two-tailed test because this is a non-directional hypotheses. The question is asking if psychology students are different, not if they are specifically more or less openness to new experiences c. What are the degrees of freedom for this z-test? Find the corresponding critical t- value for Type I error rate of a = 0.05? Degrees of Freedom: N-1= 99-1= 98 Corresponding critical t-value for Type I error rate of a = 0.05