Problem: Glass:

Glass-ceramic materials share many properties with both non-crystalline glass and crystalline ceramics. They are formed as a glass, and then partially crystallized by heat treatment. For example, the microstructure of whiteware ceramics frequently contains both amorphous and crystalline phases. Crystalline grains are often embedded within a non-crystalline intergranular phase of grain boundaries. When applied to whiteware ceramics, vitreous means the material has an extremely low permeability to liquids, often but not always water, when determined by a specified test regime.

What hardens glass-ceramics?
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A: heat treatment

Problem: The first Europeans to disembark and explore the region were the Portuguese navigators Diogo Cao in 1485 and Bartolomeu Dias in 1486; still the region was not claimed by the Portuguese crown. However, like most of Sub-Saharan Africa, Namibia was not extensively explored by Europeans until the 19th century, when traders and settlers arrived, principally from Germany and Sweden. In the late 19th century Dorsland trekkers crossed the area on their way from the Transvaal to Angola. Some of them settled in Namibia instead of continuing their journey.
In what year was Bartolmeu Dias born?
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Answer: unanswerable

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The Tennessee income tax does not apply to salaries and wages, but most income from stock, bonds and notes receivable is taxable. All taxable dividends and interest which exceed the $1,250 single exemption or the $2,500 joint exemption are taxable at the rate of 6%. The state's sales and use tax rate for most items is 7%. Food is taxed at a lower rate of 5.25%, but candy, dietary supplements and prepared food are taxed at the full 7% rate. Local sales taxes are collected in most jurisdictions, at rates varying from 1.5% to 2.75%, bringing the total sales tax to between 8.5% and 9.75%, one of the highest levels in the nation. Intangible property is assessed on the shares of stock of stockholders of any loan company, investment company, insurance company or for-profit cemetery companies. The assessment ratio is 40% of the value multiplied by the tax rate for the jurisdiction. Tennessee imposes an inheritance tax on decedents' estates that exceed maximum single exemption limits ($1,000,000 for deaths in 2006 and thereafter).
What types of income are exempt from Tennessee state income tax?
A: salaries and wages

Context and question: British television personality Anna Richardson settled a libel lawsuit in August 2006 against Schwarzenegger, his top aide, Sean Walsh, and his publicist, Sheryl Main. A joint statement read: "The parties are content to put this matter behind them and are pleased that this legal dispute has now been settled." Richardson claimed they tried to tarnish her reputation by dismissing her allegations that Schwarzenegger touched her breast during a press event for The 6th Day in London. She claimed Walsh and Main libeled her in a Los Angeles Times article when they contended she encouraged his behavior.
Who sued Schwarzenegger and two of his employees for libel, settling in 2006?
Answer: Anna Richardson

Question: Paul's Christology has a specific focus on the death and resurrection of Jesus. For Paul, the crucifixion of Jesus is directly related to his resurrection and the term "the cross of Christ" used in Galatians 6:12 may be viewed as his abbreviation of the message of the gospels. For Paul, the crucifixion of Jesus was not an isolated event in history, but a cosmic event with significant eschatological consequences, as in 1 Corinthians 2:8. In the Pauline view, Jesus, obedient to the point of death (Philippians 2:8) died "at the right time" (Romans 4:25) based on the plan of God. For Paul the "power of the cross" is not separable from the Resurrection of Jesus.
Is there an answer to this question: What term does Paul use for the Gospels?

Answer: the cross of Christ

Problem: Classical music:

Given the wide range of styles in classical music, from Medieval plainchant sung by monks to Classical and Romantic symphonies for orchestra from the 1700s and 1800s to avant-garde atonal compositions for solo piano from the 1900s, it is difficult to list characteristics that can be attributed to all works of that type. However, there are characteristics that classical music contains that few or no other genres of music contain, such as the use of a printed score and the performance of very complex instrumental works (e.g., the fugue). As well, although the symphony did not exist through the entire classical music period, from the mid-1700s to the 2000s the symphony ensembleand the works written for ithave become a defining feature of classical music.

What did not exist through the entire classical music period?
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A:
the symphony