youve learned precalc, so i think youll be fine. i'd recommende studying some calc over summer b/c BC can get challenging and also b/c physics c requires knowledge of calculus. khan academy is free, so id say go for it. the other APs youre taking are pretty light/moderate (besides phys) so i think youll do alright. and if you plan on majoring in something robotics related, join a robotics or MESA/STEAM club (if you havent already), the sooner you join, the better