Answer:
D. The last option
Explanation:
You can't divide by 0, so find out when the given function is discontinuous.
You can see that x is discontinuous at x=-1,1, so find a piecewise function that fill in those gaps.
Plug x=-1,1 into your function to find out what values you need to fill in. But of course it's discontinuous at those points, so plug in a number near x=1 and x=-1. I chose x=-1.1 and x=1.1
so we need to fill in 2 at x=-1, and fill in 4 at x=1
Since the amount of pollution emitted into the air is a very small fraction of the total material in the atmosphere, why do we have air pollution problems.
★ The burning of fossil fuels
Sulfur dioxide emitted from the combustion of fossil fuels like coal, petroleum for energy in power plants, and other factory combustibles is one the major cause of air pollution.
★ Agricultural Activities
Ammonia is a very common byproduct of agriculture-related activities and is one of the most hazardous gases in the atmosphere. The use of insecticides, pesticides, and fertilizers in agricultural activities has grown quite a lot. They emit harmful chemicals into the air and can also cause water pollution.
★ Waste in Landfills
Landfills are land areas in which waste is deposited or buried. These deposited or buried wastes generate methane. Methane is a major greenhouse gas that is highly flammable and very hazardous.
★ Exhaust from factories and industries
Manufacturing industries release a large amount of carbon monoxide, hydrocarbons, organic compounds, and chemicals into the air, thereby depleting the quality of air.
Manufacturing industries can be found at every corner of the earth, and there is no area that has not been affected by it. Petroleum refineries also release hydrocarbons and various other chemicals that pollute the air and also cause land pollution.
★ Mining Operations
Mining is a process wherein minerals below the earth are extracted using large equipment. During the process, dust and chemicals are released in the air causing massive air pollution.
This is one of the reasons which is responsible for the deteriorating health conditions of workers and nearby residents.