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Dolphin Bay was surrounded by mountains on three sides and faced the ocean on one, gradually deepening from the shores before appearing like a small lake.
Once past the mouth of the bay, the depth of Dolphin Bay would suddenly increase to over a hundred meters.
Though dolphins are skilled divers, capable of diving hundreds of meters, their main activity range is concentrated in the shallow seas between thirty and fifty meters.
Therefore, the range of Bi Fang and Mandy's task was set between ten and eighty meters—just one circle wider and they could essentially capture the full range of the dolphins' activities.
For this, they had to install over twenty cameras. It sounded like not much, but it was far from an easy job.
Radio waves suffer extreme loss in the medium, so the signal drops very rapidly.