What is the depth equivalent to one atmosphere in the ocean in feet?

The depth equivalent to one atmosphere in the ocean relates to how pressure changes with depth in different types of water. In sea water, every 33 feet of depth corresponds to an increase of one atmosphere of pressure due to the weight of the water above. This means that at a depth of approximately 33 feet in sea water, the pressure experienced is about 2 atmospheres—one from the air above the surface and one from the water.

For fresh water, being less dense than sea water, the equivalent depth to achieve the same increase in pressure is slightly greater. It takes about 34 feet of fresh water to exert the same pressure as 33 feet of sea water. This difference is crucial for divers to understand, as the type of water affects the depth at which they are operating and how pressure affects their diving experience.

Therefore, the choice that indicates 10m (33ft) in sea water and 10.4m (34ft) in fresh water accurately reflects the concepts of pressure depth in different types of water, making it the correct answer.