What do scientists estimate is the approximate age of the planet earth? a. 660 million years b. 3.5 billion years c. 4.6 billion years d. 12.2 billion years

What is a population? a. all the members of the same species living in the same ecosystem at the same time b. the number of a species living in the same ecosystem over a period of time c. the total number of organisms living in an ecosystem at a point in time d. all the members of a food web in the same ecosystem