Because if we use too much coal we are wasting fossil fuels and burning coal hurts the environment so the alternative energy sources provide clean energy
The heart has 4 chambers.
Flight; fight
The sympathetic is used to speed things up, stopping things like digestion in order to supply more blood to the heart and lungs, while the parasympathetic does the opposite; digesting food and working on internal things while the heart rate and breathing rate slow.
Answer: We are using the genus of the taxonomic ranks for that specific organism.