1.) the geologic time scale is a system of chronological dating that relates geologic structure to geologic events. it is a model because it measures and describes events and relationships in geologic history.
2.) the paleozoic period was roughly from 245 million years ago to 545 million years ago.
3.) the dinosaurs lived in the mesozoic era, specifically the triassic period, which was roughly around 230 million years ago.
4.) the first early human relatives were found roughly around d the neogene period, about 25 million years ago, and is in the cenozoic era.
