Most hydroelectric power plants have a dam and a reservoir. These structures may obstruct fish migration and affect their populations. Operating a hydroelectric power plant may also change the water temperature and the river's flow. These changes may harm native plants and animals in the river and on land. Reservoirs may cover people's homes, important natural areas, agricultural land, and archaeological sites. So building dams can require relocating people. Methane, a strong greenhouse gas, may also form in some reservoirs and be emitted to the atmosphere. Reservoir construction is "drying up" in the United States Gosh, hydroelectric power sounds great -- so why don't we use it to produce all of our power? Mainly because you need lots of water and a lot of land where you can build a dam and reservoir, which all takes a LOT of money, time, and construction. In fact, most of the good spots to locate hydro plants have already been taken. In the early part of the century hydroelectric plants supplied a bit less than one-half of the nation's power, but the number is down to about 10 percent today. The trend for the future will probably be to build small-scale hydro plants that can generate electricity for a single community. As this chart shows, the construction of surface reservoirs has slowed considerably in recent years. In the middle of the 20th Century, when urbanization was occurring at a rapid rate, many reservoirs were constructed to serve peoples' rising demand for water and power. Since Hydroelectric energy is produced by the force of falling water. The capacity to produce this energy is dependent on both the available flow and the height from which it falls. Building up behind a high dam, water accumulates potential energy. This is transformed into mechanical energy when the water rushes down the sluice and strikes the rotary blades of turbine. The turbine's rotation spins electromagnets which generate current in stationary coils of wire. Finally, the current is put through a transformer where the voltage is increased for long distance transmission over power lines.
Hydroelectric-power production in the United States and the world!
(sorry this is the second part)
Answer:. have chloroplasts and a cell wall
Explanation:All living organisms are made up of cells.some organism are made up of one cell (Unicellular) and other organism are made up of many cells(multicellular).
Cells are made up of organelles and the organelles present in a cell differ in animals cells and plant cells.
A feature that animals cells have which plant cell do not have is the presence of centrioles.
Features that plant cell have which animals cells do not have are the presence of chloroplast ,vacuole and cell walls.
Animals do not produce their food but plants do.Green Plants produce their food through chloroplast,which contains chlorophyll.
Plants has cells walls which is rigid and made up of cellulose,lignin and pectin.this rigid structure of the cell wall contributes to the rigidity of plants stems and roots.
Option A is incorrect because plant and animal cells have mitochondria.
Option B is incorrect because plants cells have both plasma membrane and cell walls.the cell wall surrounds the plasma membrane.
Option C is incorrect because plants contains Golgi apparatus and vacuole
D. You would represent a tall plant with an uppercase T and the dwarf with a lowercase t.
Answer:A well-leveled field is seen as laying the foundation for a good water management. If a field is not properly leveled, water may stagnate in the lower parts whereas higher parts may get dry due to water receding.
Explanation:
