The body cavity terms of acoelomate, pseudocoelomate and eu (true) coelomate differentiate animals within what category or categories using the older mophological descriptions?

Which statements explains what the fossil records indicates? check all that apply. a) earth is 4.5 billion years old b) many organisms have become extinct c) mammals have always existed on earth d) mass extinctions have occurred several times on earth e) the amount of water on earth has decreased over time?