What is the ruling on Friday prayer for fishermen who remain at sea for weeks? And how is the distance of their travel at sea estimated to permit Qasr (shortening prayers) and Jam' (combining prayers)?

Friday prayer is not obligatory for those who travel by sea for hunting, because they are not residents, and it is not sufficient for them. As for shortening and combining prayers, their situation must be considered: if they intend to cover the distance of shortening (approximately 83 kilometers), then shortening and combining prayers is permissible for them. However, if they do not intend a specific distance, but rather seek hunting wherever it is found, then shortening or combining prayers is not prescribed for them, because shortening requires first intending a specific place, which the wanderer lacks.