Pokemon evolve at different levels and under many different conditions, some Pokemon evolve at levels ranging from 7-55, some evolve during a trade, some evolve if they have learned a specific move, some evolve if there a specific gender, some evolve when exposed to an evolutionary stone, some evolve if there a specific gender with a evolutionary stone, some evolve during a trade while holding a specific item, some evolve if there loyal to there trainers, some don't evolve at all. Its your job to figure out how each Pokemon evolves if it does or doesn't.
It will evolve at level 48
it will evolve at level 21
Pachirisu does not evolve :(
Arbok does not evolve
level them up
level 44
at level 20
Level 40.
Level 10
level 25
Level 30
level 32