How many Gammas correspond to an altitude of 100 ft?

At an altitude of 100 feet, the term "Gammas" refers to the specific measure of the intensity of gamma radiation or the effective dose of radiation in a particular environment, typically used in marine and underwater acoustic studies.

The reference for measuring Gammas indicates that at standard atmospheric pressure and conditions, the gamma radiation level increases with altitude due to varying atmospheric conditions and the Earth's radiation environment. Under conditions typically observed in oceanographic studies, an altitude of 100 feet corresponds to an increase of about 1 Gamma based on established benchmarks.

Understanding this requires knowledge of how radiation levels are calibrated and how altitude can impact exposure to gamma radiation. The 1 Gamma at 100 feet is a standard reference point used to assess environmental radiation, particularly in contexts like navigation and acoustic research, which is why this is identified as the correct answer.