Problem: In the US, one kilowatt-hour (3.6 MJ) of electricity currently causes an average 1.34 pounds (610 g) of CO
2 emission. Assuming the average light bulb is on for 10 hours a day, a 40-watt bulb will cause 196 pounds (89 kg) of CO
2 emission per year. The 6-watt LED equivalent will only cause 30 pounds (14 kg) of CO
2 over the same time span. A building's carbon footprint from lighting can therefore be reduced by 85% by exchanging all incandescent bulbs for new LEDs if a building previously used only incandescent bulbs.
How much can a building's carbon footprint be reduced by switching to LEDs?
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Answer: 85%

Problem: Several other types of capacitor are available for specialist applications. Supercapacitors store large amounts of energy. Supercapacitors made from carbon aerogel, carbon nanotubes, or highly porous electrode materials, offer extremely high capacitance (up to 5 kF as of 2010[update]) and can be used in some applications instead of rechargeable batteries. Alternating current capacitors are specifically designed to work on line (mains) voltage AC power circuits. They are commonly used in electric motor circuits and are often designed to handle large currents, so they tend to be physically large. They are usually ruggedly packaged, often in metal cases that can be easily grounded/earthed. They also are designed with direct current breakdown voltages of at least five times the maximum AC voltage.
How many times the maximum AC voltage are AC capacitors designed to withstand?
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Answer: at least five times the maximum AC voltage

Problem: A series of low-lying annexes (largely hidden) flank both ends. Also in the square are the glass-faced Planalto Palace housing the presidential offices, and the Palace of the Supreme Court. Farther east, on a triangle of land jutting into the lake, is the Palace of the Dawn (Palacio da Alvorada; the presidential residence). Between the federal and civic buildings on the Monumental Axis is the city's cathedral, considered by many to be Niemeyer's finest achievement (see photographs of the interior). The parabolically shaped structure is characterized by its 16 gracefully curving supports, which join in a circle 115 feet (35 meters) above the floor of the nave; stretched between the supports are translucent walls of tinted glass. The nave is entered via a subterranean passage rather than conventional doorways. Other notable buildings are Buriti Palace, Itamaraty Palace, the National Theater, and several foreign embassies that creatively embody features of their national architecture. The Brazilian landscape architect Roberto Burle Marx designed landmark modernist gardens for some of the principal buildings.
What does 'Palacio da Alvorada' mean?
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Answer:
Palace of the Dawn