What makes plants beginning of the food chain?

Drive down any three characteristic of modern periodic table

Compare the valence electron configuration of the nobles gas elements seen here. what statement is correct?

Observation and experimentation have led many scientists to accept a theory about the origin of the universe. this theory is called the big bang theory. scientific evidence collected and observed by scientists around the world suggests that the universe is ever expanding from a hot and dense initial state. what makes this a scientific theory? (2 points)