1. There are so many ways of energy conservation in nature. Conservation of energy means, in different chemical processes energy is always conserved it can change only its form.There are some examples -
- conservation of sunlight energy as it converts into chemical energy which acts as food for green plants.
- conversion of kinetic energy of water into electrical energy in hydropower plants.
2. Green plants in order to produce food uses a process called photosynthesis , in which they use Co2 , O2 and sunlight. Which later converted into chemical energy as there food.
3. According to the properties of matter , the particals of matter are constantly moving and gas is a form of matter which has highest kinetic energy and we knows air itself is a mixture of gasses.Thats why air moves from place to place.
4. Fules sauh as coal and petroleum are made up the decomposition of organic matter this process takes thousands of years.
5. Don 't know clearly but i think water itself is a form of energy which is cnstantly converting from its one form to other in nature.