split ends

Q: My friend wants to cut her hair which is below her buttocks and she is complaing that it is thin and has split ends, what should we tell her? Also if she intends to cut it upto the lower part of her back, is it permissble? She says that she is doing it for growth and because it gets stuck in her buttocks. However, because shes an alimah Im telling her to do ihtiyaat since we sometimes end up taking leeways and following desires. What should I tell this girl because she keeps insisting that she wants to do it?

Q: Are we allowed to cut the split end? If so, do we just cut of from the split?

Q: Can a woman trim her hair every month for healthy hair specially to get rid of split ends?

Q: If a ladies hair is below her navel reaching the knees almost, and the bottom of her hair is dead and has something like split ends, can she trim 3cm or less? In which other circumstance can a women trim hair?