Sunlight, Water and Food.
Potential energy because when your body breaks down the molecules the energy is released that it can use to do work, like walk or think.
An athlete would have a larger vital capacity than a non-athlete aerobic ability would find people with larger lungs and hence a bigger vital capacity. The vital capacity of an athlete is higher than a non-athlete because they are trying to do hard work their legs to get bigger and bigger over time making it easier for them
They are considered so because are the indispensable parts of the nature cycle.Without formation,decay cannot be possible and similarly,formation cannot be possible without decay.In addition to this,THEY ARE IN A CHRONOLOGICAL MANNER SET BY NATURE and that's why cannot be seperated and so together constitute the cycle of nature.