There is no limit for the number of entrances in a mosque. It could be any number depending on the mosque capacity and design. At least there is one entrance!!!
There are approximately 450 mosques in the Netherlands.
all proper mosques are open everyday
there are too many mosques in Indonesia since it's one of the largest Islam population in the world.
it's not Necessary for mosques to have domes, but when they do, it depends on how big the ( Masged = mosque ) is. at least one.