Which of the six essential elements of Geography is discussed here? What information is presented that helped you determine which element is being discussed? (Site 1)

Which evidence is most likely used to indicate the beginning of solar system formation? a. materials combined to form a mass. b. materials were pulled together by gravity. c. water condensed and collected to form oceans. d. different species of microorganisms lived on earth.

How would i answer this for an exam?

Irelanda. populationb. square mileagec. average population density per square mile