What instrument is used to measure the strength of a magnetic field?

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What is the official language of Austria?

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Who wrote the Inspector Morse crime novel series?

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Lake Champlain lies on the border between Vermont and which other US state?

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With what is sulfur and charcoal mixed to make gunpowder?

On what TV show did Alanis Morrisette appear in the 1980's?

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Which city was engulfed in lava from Mount Vesuvius in AD 79?

Which impresionist artist's most important work was his series of paintings based around Hampton on the river Thames?