Answer:
<em>It is a chemical reaction in which the reactants form products and products react together to give reactants back. That means reversible reactions can go in both directions forward as well as backward direction.</em>
The circulatory and respiratory systems work together to circulate blood and oxygen throughout the body. Air moves in and out of the lungs through the trachea, bronchi, and bronchioles. Blood moves in and out of the lungs through the pulmonary arteries and veins that connect to the heart
Answer: kerosene, coal
Explanation:
These are renewable resources obtained from petroleum, kerosene was used in olden times to light the lamps and are still used today for lighting purposes. Coal was used in trains to produce steam( steam powered trains).