Haruki hears about Kazusa's moving from her mother, who she hadn't been on good terms with.  He feels betrayed and angrily confronts her.  But his words force open the door to Kazusa's heart, which she had desperately tried to keep closed so that the three of them could stay together.
or how much her mother's 
donated to this school.
und wie viel sie dieser Schule gespendet hat.
o cuánto haya donado a esta escuela.
o cuánto haya donado a esta institución.
offre une contribution 
importante à l’école,
ou quanto ela já doou para o colégio.