Problem: High-definition television:

A very high resolution source may require more bandwidth than available in order to be transmitted without loss of fidelity. The lossy compression that is used in all digital HDTV storage and transmission systems will distort the received picture, when compared to the uncompressed source.

A very high resolution source may require more of what?
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A: bandwidth

Problem: Black people:

Numerous communities of dark-skinned peoples are present in North Africa, some dating from prehistoric communities. Others are descendants of the historical Trans-Saharan trade in peoples and/or, and after the Arab invasions of North Africa in the 7th century, descendants of slaves from the Arab Slave Trade in North Africa.

When were the Arab Invasions?
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A: the 7th century

Problem: United States presidential election, 2004:

The second presidential debate was held at Washington University in St. Louis, Missouri, on October 8, moderated by Charles Gibson of ABC. Conducted in a town meeting format, less formal than the first presidential debate, this debate saw Bush and Kerry taking questions on a variety of subjects from a local audience. Bush attempted to deflect criticism of what was described as his scowling demeanor during the first debate, joking at one point about one of Kerry's remarks, "That answer made me want to scowl."

How did Bush try to make light of himself after being made fun of for his demeanor during the first debate?
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A: joking at one point about one of Kerry's remarks, "That answer made me want to scowl."

Problem: Alloy:

At a certain temperature, (usually between 1,500 F (820 C) and 1,600 F (870 C), depending on carbon content), the base metal of steel undergoes a change in the arrangement of the atoms in its crystal matrix, called allotropy. This allows the small carbon atoms to enter the interstices of the iron crystal, diffusing into the iron matrix. When this happens, the carbon atoms are said to be in solution, or mixed with the iron, forming a single, homogeneous, crystalline phase called austenite. If the steel is cooled slowly, the iron will gradually change into its low temperature allotrope. When this happens the carbon atoms will no longer be soluble with the iron, and will be forced to precipitate out of solution, nucleating into the spaces between the crystals. The steel then becomes heterogeneous, being formed of two phases; the carbon (carbide) phase cementite, and ferrite. This type of heat treatment produces steel that is rather soft and bendable. However, if the steel is cooled quickly the carbon atoms will not have time to precipitate. When rapidly cooled, a diffusionless (martensite) transformation occurs, in which the carbon atoms become trapped in solution. This causes the iron crystals to deform intrinsically when the crystal structure tries to change to its low temperature state, making it very hard and brittle.

Soft and bendable steel is caused by what?
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A:
If the steel is cooled slowly