Problem: Madonna (entertainer):

In 2012, Madonna performed at Super Bowl XLVI halftime show, visualized by Cirque Du Soleil and Jamie King and featured special guests LMFAO, Nicki Minaj, M.I.A. and Cee Lo Green. It became the then most-watched Super Bowl halftime show in history with 114 million viewers, higher than the game itself. It was also revealed that the singer had signed a three-album deal with Interscope Records, who would act as the distributor in partnership with her 360 deal with Live Nation. Her twelfth studio album, MDNA, was released in March 2012 and saw collaboration with various producers, most notably with William Orbit again and Martin Solveig. The album was well received by music critics, with Priya Elan from NME calling it "a ridiculously enjoyable romp", citing its "psychotic, soul-bearing stuff" as "some of the most visceral stuff she's ever done." MDNA debuted at number one on the Billboard 200 and many other countries worldwide. Madonna surpassed Elvis Presley's record for the most number-one album by a solo artist in the UK. The lead single "Give Me All Your Luvin'", featuring guest vocals from Minaj and M.I.A., became Madonna's record-extending 38th top-ten hit on the Billboard Hot 100.

What was the name of Madonna's twelfth album?
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A: MDNA


Problem: Police:

The terms international policing, transnational policing, and/or global policing began to be used from the early 1990s onwards to describe forms of policing that transcended the boundaries of the sovereign nation-state (Nadelmann, 1993), (Sheptycki, 1995). These terms refer in variable ways to practices and forms for policing that, in some sense, transcend national borders. This includes a variety of practices, but international police cooperation, criminal intelligence exchange between police agencies working in different nation-states, and police development-aid to weak, failed or failing states are the three types that have received the most scholarly attention.

When did Nadelmann write about global policing?
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A: 1993


Problem: Marshall Islands:

Subsequently, seven other chiefs on seven other islands signed a treaty in German and Marshallese and a final copy witnessed by Rötger on November 1 was sent to the German Foreign Office. The Germans erected a sign declaring a "Imperial German Protectorate" at Jaluit. It has been speculated that the crisis over the Carolines with Spain, which almost provoked a war, was in fact "a feint to cover the acquisition of the Marshall Islands", which went almost unnoticed at the time, despite the islands being the largest source of copra in Micronesia. Spain sold the islands to Germany in 1884 through papal mediation.

In what year did Germany buy the Marshalls from Spain?
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A: 1884


Problem: Hydrogen:

Hydrogen is highly soluble in many rare earth and transition metals and is soluble in both nanocrystalline and amorphous metals. Hydrogen solubility in metals is influenced by local distortions or impurities in the crystal lattice. These properties may be useful when hydrogen is purified by passage through hot palladium disks, but the gas's high solubility is a metallurgical problem, contributing to the embrittlement of many metals, complicating the design of pipelines and storage tanks.

Where can you find soluble hydrogen?
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A:
nanocrystalline and amorphous metals