Problem: Light-emitting diode:

White light can be formed by mixing differently colored lights; the most common method is to use red, green, and blue (RGB). Hence the method is called multi-color white LEDs (sometimes referred to as RGB LEDs). Because these need electronic circuits to control the blending and diffusion of different colors, and because the individual color LEDs typically have slightly different emission patterns (leading to variation of the color depending on direction) even if they are made as a single unit, these are seldom used to produce white lighting. Nonetheless, this method has many applications because of the flexibility of mixing different colors, and in principle, this mechanism also has higher quantum efficiency in producing white light.[citation needed]

What colors are used to form white light?
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A: red, green, and blue

Problem: Renewable energy commercialization:

Renewable energy is also the most economic solution for new grid-connected capacity in areas with good resources. As the cost of renewable power falls, the scope of economically viable applications increases. Renewable technologies are now often the most economic solution for new generating capacity. Where "oil-fired generation is the predominant power generation source (e.g. on islands, off-grid and in some countries) a lower-cost renewable solution almost always exists today". As of 2012, renewable power generation technologies accounted for around half of all new power generation capacity additions globally. In 2011, additions included 41 gigawatt (GW) of new wind power capacity, 30 GW of PV, 25 GW of hydro-electricity, 6 GW of biomass, 0.5 GW of CSP, and 0.1 GW of geothermal power.

What is the most economic solution for old grid-connected capacity in areas with good resources?
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A: unanswerable

Problem: Light-emitting diode:

The light from LEDs can be modulated very quickly so they are used extensively in optical fiber and free space optics communications. This includes remote controls, such as for TVs, VCRs, and LED Computers, where infrared LEDs are often used. Opto-isolators use an LED combined with a photodiode or phototransistor to provide a signal path with electrical isolation between two circuits. This is especially useful in medical equipment where the signals from a low-voltage sensor circuit (usually battery-powered) in contact with a living organism must be electrically isolated from any possible electrical failure in a recording or monitoring device operating at potentially dangerous voltages. An optoisolator also allows information to be transferred between circuits not sharing a common ground potential.

Where are LEDs not often used?
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A: unanswerable

Problem: CBC Television:

Beginning in 2005, the CBC has contributed production funds for the BBC Wales revival of Doctor Who, for which it received a special credit at the end of each episode. This arrangement continued until the end of fourth season, broadcast in 2008. The CBC similarly contributed to the first season of the spin-off series, Torchwood. More recently, the network has also begun picking up Canadian rights to some Australian series, including the drama series Janet King and Love Child, and the comedy-drama series Please Like Me.

What year did the CBC begin contributing funds to the show Doctor Who?
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A:
2005