Answer:
#1: They all need food, water, air, a place to live.
#2: It proves it by explaining how certain chemical reactions/events that caused this to be proven that it wasn't spontaneous and it was more of evolution.
#3: They need these things because it is essential and without it plants and animals wouldn't have a way to survive the natural events and natural ways of life or how to live.
#4: It allows them to keep warmth in the slimmest of spots, such as how we have fingers they can freeze quickly, well so can an animals paws. It can also help with some other things that they would traditionally do such as climbing.
Step-by-step explanation:
If these answers are non-sufficient to your question then i take some blame and i did try my hardest to answer these questions to the best of my ability.