What is the struggle for food, space and other limited resources called?

Gabriel is at a stage where his body is changing physically; he is growing facial hair and building muscle. he is also just starting to make sperm. what is most likely gabriel’s age? 5 12 17 21

Prompt compare the three types of volcanic mountains in terms of shape, type of eruption, and the minerals that make up the volcano

Penelope studies how the structure and function of the nervous system is related to behavior. she is a psychologist