Which preservative has been found to be potentially carcinogenic in animals?

Up until 1938, paleontologists accepted the idea that coelacanths (an ancient fish) went extinct at the time that they last appear in the fossil record, about 80 million years ago. but in 1938, a live coelacanth was discovered off the coast of south africa that was compared to the fossil record and found to be the same species what goal of science does this discovery represent

Any sound above what db can cause hearing loss in human beings

Explain how scientists use geologic time to determine the age of landforms.