Question

what are the  three variables that affect a living system?

Answer 1

three variables that can affect the living system are:
1 environment
2 temperature
3 food
importance:
all these can help to develop a living circle but if balance is destroyed .. they can destroy a fully developed ecosystem..

Answer 2

environment which includes temperature and obstacles
food which includes hunger, thirst, etc.
competition to find food, land, and even for mating.