Aproper cool-down routine does which of the following?

Explain to someone who knows nothing about fossils the study of invertebrate paleontology and how it scientists understand the history of the earth. be sure your explanation contains a minimum of two complete sentences.

Aball of mass 0.3kg is released from rest at a height of 8m. how fast is it going when it hits the ground? accleration due to gravity is g=9.8m/s

Using a caesar cypher with an offset of three characters (a -> d, b -> e, z -> c), what would be the correct cypher text for the plain text "attack at dawn"?