Conceptually, one can define three generations of renewables technologies, reaching back more than 100 years .
First-generation technologies emerged from the industrial revolution at the end of the 19th century and include hydropower, biomass combustion and geothermal power and heat. Some of these technologies are still in widespread use.
Second-generation technologies include solar heating and cooling, wind power, modern forms of bioenergy and solar photovoltaics. These are now entering markets as a result of research, development and demonstration (RD&D) investments since the 1980s. The initial investment was prompted by energy security concerns linked to the oil crises (1973 and 1979) of the 1970s but the continuing appeal of these renewables is due, at least in part, to environmental benefits. Many of the technologies reflect significant advancements in materials.
Third-generation technologies are still under development and include advanced biomass gasification, biorefinery technologies, concentrating solar thermal power, hot dry rock geothermal energy and ocean energy. Advances in nanotechnology may also play a major role.
Answer:
Option (2) and (3).
Explanation:
Cancer is the uncontrolled division of the cell that might results in the loss of apoptosis in the cells. The cancer cell shows the property like angiogenesis and loss of contact inhibition.
Both the hereditary factors like mutations in some gene and environmental factors like any mutagen may inhibit the process of the cell division. Both these factors mainly inhibits the gene that are responsible for the regulation of the cell cycle like p53, Rb.
Thus, the correct answer is option (2) and (3).
Answer:
I think it is B.
Explanation:
Hope my answer has helped you!
Answer: Aquifers that are drying up are mainly near arid climates, large cities, or agricultural stations, like farms.if the aquifer is shallow enough and permeable enough to allow water to move through it at a rapid-enough rate, then people can drill wells into it and withdraw water Excessive pumping can lower the water table so much that the wells no longer supply water they can "go dry."
The answer here would be number 3, photosynthesis can e explained with the equation <span> carbon dioxide + water —> glucose + oxygen + water, this means that plants use light to convert carbon dioxide into carbohydrates or as you put it enery rich glucose molecules, this is the way plants make there food </span>
