Question

two divers are diving in clear ocean water at a depth of 175 m. one diver shows a white marker board to the other with writing on it. what color will the marker board appear to be? blue violet orange red

Explanation:

When light travels through water, different wavelengths (colors) are absorbed at different rates. Longer - wavelength colors like red are absorbed more quickly. At a depth of 175 m, red, orange, and other longer - wavelength colors have been mostly absorbed. Blue has a shorter wavelength and is absorbed less at this depth. A white object reflects all colors of light. But since red, orange, etc., are no longer present in the light reaching the object (because they've been absorbed by the water), the white marker board will reflect the remaining color in the light, which is blue.

Answer:

blue