1. I'm trying to find the probability P(A1,A3|A2) using Bayes' rule with the aim of using P(A1,A3|A2)=P(A2|A1,A3)*P(A1,A3)/P(A2).

2. How would I compute P(A1 union A2) = P(A1) P(A2) - P(A2|A1)P(A1)?

I'm working with this data set