Energy is the power we use for transportation, for heat and light in our homes and for the manufacture of all kinds of products. There are two sources of energy: renewable and nonrenewable energy.
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Nonrenewable Sources of Energy</span>Most of the energy we use comes from fossil fuels, such as coal, natural gas and petroleum. Uranium is another nonrenewable source, but it is not a fossil fuel. Uranium is converted to a fuel and used in nuclear power plants. Once these natural resources are used up, they are gone forever.
Renewable Sources of Energy
Renewable sources of energy can be used over and over again. Renewable resources include solar energy, wind, geothermal energy, biomass and hydropower. They generate much less pollution, both in gathering and production, than nonrenewable sources.
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Always remember quadrilateral means 4 sides
Answer:
Walking
Explanation:
A muscle cell usually contracts or expands simultaneously when one is working or doing some activities like running, exercises, house chores e.t.c
Muscles are flexible fibers that are very essential appendages for locomotion in human beings.
For muscle cells to contract, they are pulled together thereby causing tension in the muscle. When they are relaxed, they move away from one another.