Problem: Incandescent light bulb:

Since incandescent light bulbs use more energy than alternatives such as CFLs and LED lamps, many governments have introduced measures to ban their use, by setting minimum efficacy standards higher than can be achieved by incandescent lamps. Measures to ban light bulbs have been implemented in the European Union, the United States, Russia, Brazil, Argentina, Canada and Australia, among others. In the Europe the EC has calculated that the ban contributes 5 to 10 billion euros to the economy and saves 40 TWh of electricity every year, translating in CO2 emission reductions of 15 million tonnes.

How are laws written that bring about a ban of incandescent light bulbs?
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A: by setting minimum efficacy standards higher than can be achieved by incandescent lamps


Problem: American Idol:

The American Idol Songwriter contest was also held this season. From ten of the most popular submissions, each of the final two contestants chose a song to perform, although neither of their selections was used as the "coronation song". The winning song, "The Time of My Life", was recorded by David Cook and released on May 22, 2008.

How was the winning single chose on season seven of American Idol?
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A: The American Idol Songwriter contest


Problem: Dissolution of the Soviet Union:

In Kazakhstan on June 19, 1989, young men carrying guns, firebombs, iron bars and stones rioted in Zhanaozen, causing a number of deaths. The youths tried to seize a police station and a water-supply station. They brought public transportation to a halt and shut down various shops and industries. By June 25, the rioting had spread to five other towns near the Caspian Sea. A mob of about 150 people armed with sticks, stones and metal rods attacked the police station in Mangishlak, about 90 miles from Zhanaozen, before they were dispersed by government troops flown in by helicopters. Mobs of young people also rampaged through Yeraliev, Shepke, Fort-Shevchenko and Kulsary, where they poured flammable liquid on trains housing temporary workers and set them on fire.

What did the rioters try to take over?
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A: police station and a water-supply station


Problem: Mexico City:

The World Bank has sponsored a project to curb air pollution through public transport improvements and the Mexican government has started shutting down polluting factories. They have phased out diesel buses and mandated new emission controls on new cars; since 1993 all new cars must be fitted with a catalytic converter, which reduces the emissions released. Trucks must use only liquefied petroleum gas (LPG). Also construction of an underground rail system was begun in 1968 in order to help curb air pollution problems and alleviate traffic congestion. Today it has over 201 km (125 mi) of track and carries over 5 million people every day. Fees are kept low to encourage use of the system and during rush hours the crush is so great, that authorities have reserved a special carriage specifically for women. Due to these initiatives and others, the air quality in Mexico City has begun to improve, with the air becoming cleaner since 1991, when the air quality was declared to be a public health risk for 355 days of the year.[citation needed]

How many days of the year in 1991 was the air pollution a serious health risk?
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A:
355