Final answer:
Berthing tents are spaced at least 35 meters apart to enhance safety and operational efficiency in underwater environments that require meticulous planning and the use of mobile guide lines for orientation.
Step-by-step explanation:
Berthing tents are placed at least 35 meters apart to ensure safety and operational efficiency during missions. The spacing is likely due to the need for careful planning in zones with an irregular bottom, and the presence of features like Caulerpa colonies that can affect navigation and orientation. By having tents spaced out, it reduces the risk of confusion and interference in areas where mobile guide lines are used to create corridors for divers to inspect and treat the seabed. The dispersal of tents thus complements the methodical approach required in such complex underwater environments.