1. why isn't solar energy usually the only power source for a region?
2. wind farms can also be used for which other purposes?
3. using hydro energy often requires that people build what?
4. what type of dangerous waste is produced by nuclear power plants
5. what is biomass?
6. what is carbon capture and storage?
7. what is energy reduction?
8. list at least two ways in which people can conserve energy.
9. how do smart grids use timing to determine electricity prices?

1.Because solar energy does require a lot of land to generate a lot of electricity, which keeps this land from being used for something else. Solar energy is usually not the only power source for a region because solar energy isn't available during all periods of time.
2. land with wind turbines on it can often at the same time be used for grazing cattle or for farming.
3. Most hydroelectricity is produced when a river flows through a dam. As the water flows through the dam, it passes through a hydraulic turbine that changes the hydro energy into electricity. 
4. In terms of radioactivity, the major source arising from the use of nuclear reactors to generate electricity comes from the material classified as HLW. Highly radioactive fission products and transuranic elements are produced from uranium and plutonium during reactor operations, and are contained within the used fuel.
5. Biomass fuels provided about 5% of the primary energy used in the United States in 2016. Of that 5%, about 48% was from biofuels (mainly ethanol), 41% was from wood and wood-derived biomass, and about 11% was from the biomass in municipal waste.
6. Carbon capture and storage, or CCS, is a family of technologies and techniques that enable the capture of carbon dioxide (CO2) from fuel combustion or industrial processes, the transport of CO2 via ships or pipelines, and its storage underground, in depleted oil and gas fields and deep saline formations
7. Efficient energy use, sometimes simply called energy efficiency, is the goal to reduce the amount of energy required to provide products and services
8. Use kitchen, bath and other ventilating fans sparingly. Leaving them on too long will suck away a tremendous amount of household heat. Turn them off when their job is complete. Turn down your thermostat at night or when you’re away for more than four hours during the day. Do not turn off your heating system entirely as this may cause pipes to freeze.
9. Just as the internet enabled interactive, two-way communication, the smart grid, we’re told, will deploy sensors and software to digitize a century-old analog electricity distribution system, transforming it into one capable of integrating renewable energy and decentralizing power production.

Cprogram to find //perimeter of rectangle printf(" \n perimeter of rectangle \n"); printf(""); printf("\n enter width and length of the rectangle : "); scanf("%f%f", & width,& length); perimeter = 2 * (width + length); printf("perimeter of rectangle is: %.3f", perimeter);