What best describes index fossils? Organisms that existed over a limited period Organisms whose age is hard to detect Fossils that are used in radioactive dating Fossils of the most ancient organisms

i think its fossils that are sued in radioactive dating because index fossils are fossils that are useful for dating and correlating the strata in which it is found, and radioactive dating is the only option that has to do with finding time.

Explanation

i'm not sure at all please do a little more research before putting my answer down

think about the oscillation of the toy shown in the video. when the toy is at the highest point of its motion, its velocity is zero and its acceleration is negative.

the skeletons of most mammals reach a certain size and then stop growing. however, many animals, including some mammals, keep growing throughout their lives. kangaroos, for example, just keep growing and growing until they die. also, the longer an animal lives the greater the chance it might catch some deadly disease.