Student State Residency

We live in PA. My daughter was a student in ID for the 2020 spring semester and had a part-time job (1st W2). In March she came home due to Covid shutdown and worked over the summer in PA (2nd W2). In August she moved to ID to establish residency (taking a gap year and then re-entering school as in-state) and is working full-time (3rd W2). 

1. Can I claim her as a dependent (I did provide more than half of her living expenses in 2020)?

2. What is her state of residency (PA or ID since she moved there in August)?

3. What state(s) does she need to file income taxes in? 

Thank you!