8. In a t test for dependent means in which 10 participants are each tested twice, the number of degrees of freedom is (Give a number.) 9. You are evaluating a non-directional hypothesis at the .01 significance level using a t test for a single sample. If there are 16 people in the sample, the cutoff score (critical value) needed is 10. You are evaluating a directional hypothesis at the .05 significance level using a t test for a single sample. If there are 20 people in the sample, the cutoff score (critical value) needed is 11. Testing participants before and after an experimental manipulation is called a(n) design. 12. Since a t test for independent means may be used when Sample 1 and Sample 2 include different numbers of participants, the two estimates of the population variance are combined into an overall pooled estimate using a (what type of equation are we using)