Problem: Hard rock:

Hard rock entered the 1990s as one of the dominant forms of commercial music. The multi-platinum releases of AC/DC's The Razors Edge (1990), Guns N' Roses' Use Your Illusion I and Use Your Illusion II (both in 1991), Ozzy Osbourne's No More Tears (1991), and Van Halen's For Unlawful Carnal Knowledge (1991) showcased this popularity. Additionally, The Black Crowes released their debut album, Shake Your Money Maker (1990), which contained a bluesy classic rock sound and sold five million copies. In 1992, Def Leppard followed up 1987's Hysteria with Adrenalize, which went multi-platinum, spawned four Top 40 singles and held the number one spot on the US album chart for five weeks.

Which Def Leppard 1987 album held the number one spot in the British charts for five weeks?
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A: unanswerable

Problem: Hunter-gatherer:

Lee and Guenther have rejected most of the arguments put forward by Wilmsen. Doron Shultziner and others have argued that we can learn a lot about the life-styles of prehistoric hunter-gatherers from studies of contemporary hunter-gatherersespecially their impressive levels of egalitarianism.

What is it about prehistoric hunter-gatherers that impresses Shultziner?
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A: egalitarianism

Problem: Germans:

In 1866, the feud between Austria and Prussia finally came to a head. There were several reasons behind this war. As German nationalism grew strongly inside the German Confederation and neither could decide on how Germany was going to be unified into a nation-state. The Austrians favoured the Greater Germany unification but were not willing to give up any of the non-German-speaking land inside of the Austrian Empire and take second place to Prussia. The Prussians however wanted to unify Germany as Little Germany primarily by the Kingdom of Prussia, whilst excluding Austria. In the final battle of the German war (Battle of Koniggratz) the Prussians successfully defeated the Austrians and succeeded in creating the North German Confederation.

When did the strife between Austria and Prussia erupt?
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A: 1866

Problem: Josip Broz Tito:

After the constitutional changes of 1974, Tito began reducing his role in the day-to-day running of the state. He continued to travel abroad and receive foreign visitors, going to Beijing in 1977 and reconciling with a Chinese leadership that had once branded him a revisionist. In turn, Chairman Hua Guofeng visited Yugoslavia in 1979. In 1978, Tito traveled to the U.S. During the visit strict security was imposed in Washington, D.C. owing to protests by anti-communist Croat, Serb and Albanian groups.

In what year did Tito travel to China to reconcile with Chinese leadership?
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A:
1977