Breathing in air pollutants can irritate your airways. It may cause shortness of breath, coughing, wheezing, asthma episodes and chest pain. Overtime, exposure to air pollution puts you at risk for lung cancer, heart attack/strokes, etc. Some people are more at risks from others though
Because some energy is lost as heat,sound etc
I’m leanings towards A but it may also be B.
The most significant uses of coal are in electricity generation, steel production, cement manufacturing and as a liquid fuel. Steam coal - also known as thermal coal - is mainly used in power generation.