Problem: Infrared:

In infrared photography, infrared filters are used to capture the near-infrared spectrum. Digital cameras often use infrared blockers. Cheaper digital cameras and camera phones have less effective filters and can "see" intense near-infrared, appearing as a bright purple-white color. This is especially pronounced when taking pictures of subjects near IR-bright areas (such as near a lamp), where the resulting infrared interference can wash out the image. There is also a technique called 'T-ray' imaging, which is imaging using far-infrared or terahertz radiation. Lack of bright sources can make terahertz photography more challenging than most other infrared imaging techniques. Recently T-ray imaging has been of considerable interest due to a number of new developments such as terahertz time-domain spectroscopy.

What devices are often equipped with infrared blockers?
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A: Digital cameras


Problem: Greeks:

Greek demonstrates several linguistic features that are shared with other Balkan languages, such as Albanian, Bulgarian and Eastern Romance languages (see Balkan sprachbund), and has absorbed many foreign words, primarily of Western European and Turkish origin. Because of the movements of Philhellenism and the Diafotismos in the 19th century, which emphasized the modern Greeks' ancient heritage, these foreign influences were excluded from official use via the creation of Katharevousa, a somewhat artificial form of Greek purged of all foreign influence and words, as the official language of the Greek state. In 1976, however, the Hellenic Parliament voted to make the spoken Dimotiki the official language, making Katharevousa obsolete.

 What did these changes not highlight?
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A: unanswerable


Problem: Detroit:

Detroit Medical Center formally became a part of Vanguard Health Systems on December 30, 2010, as a for profit corporation. Vanguard has agreed to invest nearly $1.5 B in the Detroit Medical Center complex which will include $417 M to retire debts, at least $350 M in capital expenditures and an additional $500 M for new capital investment. Vanguard has agreed to assume all debts and pension obligations. The metro area has many other hospitals including William Beaumont Hospital, St. Joseph's, and University of Michigan Medical Center.

What is a name of a Catholic hospital in Detroit?
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A: St. Joseph's


Problem: Architecture:

The earliest surviving written work on the subject of architecture is De architectura, by the Roman architect Vitruvius in the early 1st century AD. According to Vitruvius, a good building should satisfy the three principles of firmitas, utilitas, venustas, commonly known by the original translation – firmness, commodity and delight. An equivalent in modern English would be:

When did Vitruvius create these plans?
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A:
1st century AD.