Student 4 is correct. The farther the planet is from the Sun, the less pull it exerts on it.
O1:2:1 because they are carbon, hydrogen and oxygen
Resident 1 is to give the most valid results.
Explanation:
In a food chain, only 10% of energy is transferred from one trophic level to another trophic level. If the energy produced at the producer level is 1000 J, then the energy available at the primary consumer level will be 100 J and energy available at the secondary consumer level will be 10 J.
Any condition in an experiment that can be changed is a control variable!!
You control it!!