A biological system is a complex network of biologically relevant entities. ... Examples of biological systems at the macro scale are populations of organisms. On the organ and tissue scale in mammals and other animals, examples include the circulatory system, the respiratory system, and the nervous system. source: google
B - The environment within the cell is stable.
Homeostasis is when your body works to maintain equilibrium (balance) so within a cell, the cell would be stable
Answer:
Rays having same endpoint E but not in the opposite directions are ED and EC. This pair of rays meet at point E having different directions.
