statistics help please

I'm having trouble with a few questions in my text book and was hoping you could help...I need to know this for my exam and I just need some help figuring these out...the first one is

1. A two-factor research study has two levels of factor A and two levels of factor B with n = 10 participants in each treatment condition. For this study, what is the value for dfbetween treatments?
2. For an experiment involving 2 levels of factor A and 3 levels of factor B, with a sample of n = 10 in each treatment condition, what are the df values for the F-ratio for the A x B interaction?

3. For the following data, compute the Pearson correlation:
2 0
3 1
7 4
5 6
4 6
3 1