Deleted 01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/03.reflexion-refraction-raytracing/04.reflexion-refraction-overview/07.reflexion-refraction-level-up/portal.en.md, 01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/03.reflexion-refraction-raytracing/04.reflexion-refraction-overview/07.reflexion-refraction-level-up/portal.es.md, 01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/03.reflexion-refraction-raytracing/04.reflexion-refraction-overview/07.reflexion-refraction-level-up/portal.fr.md files