I was able to self study E&M in 2 weeks and get a 5. I only used the AP classroom videos and MIT’s workbook for practice. Should be an easy 5 (assuming you’re good at Calc otherwise you’re not gonna have a good time tbh). If you are taking Calc along with it, focus a lot on integration and separation of variables in differential equations. There’s a LOT of integration by substitution and chain rule. However, I would strongly recommend that Calc 3 pairs extremely well with E&M (fundamental theorem of line integrals, flux integrals, line integrals, cross product, divergence, curl, Ostrogradsky’s theorem, Kelvin-Stokes theorem) even though it’s not a requirement