Answer:
A. Mass-extinction events are times in the Earth's history when few species evolve.
Explanation:
The extinction that occurred 65 million years ago wiped out some 50 percent of plants and animals. The event is so striking that it signals a major turning point in Earth's history, marking the end of the geologic period known as the Cretaceous and the beginning of the Tertiary period.
A wide range of animals and plants suddenly died out, from tiny marine organisms to large dinosaurs.
Species go extinct all the time. Scientists estimate that at least 99.9 percent of all species of plants and animals that ever lived are now extinct.
FBD provides a visual for every force that the object experiences. It can tell you the direction by showing the direction and magnitude of the forces. You can calculate the net force, example being that the applied force is 300N and the force of friction is 100N, the net force is 200N in the direction of the applied force. (Fnet= Fa- Ff).
True, I'm not the best when it comes to science, but I'm pretty sure it's this
