Commanding officer's permission is required when operating SONAR within what height above bottom?

The correct answer is 50 feet because operational guidelines and safety protocols in naval operations often set specific depths at which certain equipment, like SONAR, can be used without special authorization. The need for the commanding officer's permission typically arises from concerns about safety, environmental impact, and operational security, especially when sonar systems are deployed close to the seabed. At heights above the bottom of 50 feet, the risk of interference with marine life, seabed structures, or other environmental factors increases, prompting the requirement for oversight and permission from a commanding officer to ensure responsible use of sonar systems within that critical range.