You should study earth science because you will learn how scientists can determine how old rocks are and you will know about the earth better.
The biggest problems, with most important first, are: human numbers, carbon-dioxide-driven warming and acidification, overfishing, and plastics.
A freshwater food fish of the Northern Hemisphere. It has a long snout and can be 1.2 meters long. (Could also be called a Northern Pike)
Panama is an isthmus linking central and south america.