t = r n − 2 1 − r 2 = 0.45 25 − 2 1 − 0.45 2 = 2.417 The critical value for α = 0.05 for a two-tailed test using the t 24 distribution is 2.064. Your value is greater than this, so you reject the null hypothesis and conclude that the study produced evidence that the variables are significantly correlated
The volume is multiplied by 8. For example if you have a 1x1x1 cube the volume is 1. If you have a 2x2x2 cube the volume is 8. If you have a 4x4x4 the volume is 64.
