What is the ruling on displaying commercial advertisements on the bulletin board inside the mosque, and announcing worldly matters via loudspeakers?

Placing advertisements in mosques falls into three categories: First, advertisements guiding to good deeds, such as the opening of an Islamic kindergarten, which is permissible. Second, advertisements about a permissible matter, such as postponing a wedding, which is not problematic, provided it serves a general benefit, though it is preferable to avoid it if possible. Third, commercial promotional advertisements, which mosques should be kept free from, as they distract people and because mosques were not built for such purposes, even though it is not a forbidden sale according to Sharia.