Answer: To know if a document is a primary source, check to see when the document is published, if it is an autobiography of a person, a diary, a letter, or the documents happen at the time of the event.
The competition between two organisms can be seen if there is only 1 source of food or habitat space and they're competing against each other for the food or habitat.
There is cooperation between two organisms if they are helping each other with resources or alarming each other if there is danger.
Predation between two organisms happen when one organism hunts the other organism for food.
Relative dating best helps determine fossil age. It's where layers of sedimentary rock and fossils pile up on top of each other; the oldest fossils being in the bottom layer and the youngest in the top.
<span>The total number of genes present in a population is called the gene pool. Hope this helps </span>
The heart has 4 chambers.
