toxic exposure, surface impacts, and underwater noise
toxic exposure (pollution), surface impacts (fishing, boating), and underwater noise because Orcas communicate with each other over short and long distances with a variety of clicks, chirps, squeaks and whistles, along with using echolocation to locate prey and to navigate. They may also rely on passive listening as a primary sensory source.
Density and solubility are similar because they both involve water, but they are different because density involves dissolving a material and solubility involves floating or sinking a material.
