Answer: d. all the above
Natural resources can be classified into two main types:
1.Renewable resources
2.Non-renewable resources
Renewable resources are those which can be replenished and reused. These resources are abundantly present in the nature. Example wind, biomass. Non-renewable resources are those which cannot be replenished after single time use. Example fossil fuels, groundwater, natural gases, forests. These resources needs to be conserved and their use should be judicious. Government should participate to prevent excess and destructive use of natural resources. Such as it should prevent deforestation. Many buisnesses requires the use of fossil fuels and natural gases which should be limited as these resources takes several years to be produced under the heap of earth. Citizens should prevent the use of groundwater in excess as this is the water reservoir which takes many years to be filled by natural means such as rain, agricultural irrigation, river and lakes.
Answer:
2.7 billion
Explanation:
This period is referred to as the Great Oxygenation Event. This period saw the evolution of photosynthetic organisms (cyanobacteria) that utilized carbon dioxide (that dominated the atmosphere then) and sunlight to manufacture their energy molecules-glucose. Photosynthesis produces oxygen as a byproduct that is evolved into the atmosphere. As these photosynthetic organisms proliferated on earth, the atmosphere composition changed to become partly dominated by oxygen (which is an oxidaton agent) with less and less carbon dioxide.
