Why do researchers think that seals use visual cues to
navigate?

Their vision underwater is better than a humans, but inferior on land. Lenses are enlarged and almost round, adapted for focusing on light that is refracted upon entering water. They use the light to continue swimming which is why researchers think they use visual cues because of how quickly they react to the amount of light in the water

the rocks are classified by the geological process they are formed by. the three main groups of rocks are igneous, metamorphic, and sedimentary. minerals are not they are classified under the chemical classes they are in. these groups include silicates, sulfates and carbonates.