Because of the reduction in individual differences, a within-subjects design has _____ statistical power than a between-subjects designs.

If a correlated groups t test has 35 participants, the degrees of freedom is? (solve and put numerical value as your answer):

Practice and fatigue effects common to multiple testing can be reduced and/or controlled for by _____, which means to systematically vary the order of the conditions for subjects in a within-subjects experiment.

If you are conducting a within subjects design with two conditions and want 50 participants in each condition, how many participants total do you need?