Question: Infrared radiation is used in industrial, scientific, and medical applications. Night-vision devices using active near-infrared illumination allow people or animals to be observed without the observer being detected. Infrared astronomy uses sensor-equipped telescopes to penetrate dusty regions of space, such as molecular clouds; detect objects such as planets, and to view highly red-shifted objects from the early days of the universe. Infrared thermal-imaging cameras are used to detect heat loss in insulated systems, to observe changing blood flow in the skin, and to detect overheating of electrical apparatus.
Is there an answer to this question: What technology is used by night-vision devices?

Answer: active near-infrared illumination


Question: Arsenal was the first club from the south of England to join The Football League, in 1893. They entered the First Division in 1904, and have since accumulated the second most points. Relegated only once, in 1913, they continue the longest streak in the top division. In the 1930s, Arsenal won five League Championships and two FA Cups, and another FA Cup and two Championships after the war. In 1970–71, they won their first League and FA Cup Double. Between 1988 and 2005, they won five League titles and five FA Cups, including two more Doubles. They completed the 20th century with the highest average league position.
Is there an answer to this question: How many league championships did Arsenal win in the 1930s?

Answer: five


Question: Pain is the most common reason for people to use complementary and alternative medicine. An analysis of the 13 highest quality studies of pain treatment with acupuncture, published in January 2009, concluded there is little difference in the effect of real, sham and no acupuncture. However other reviews have found benefit. Additionally, there is tentative evidence for a few herbal medicine. There is interest in the relationship between vitamin D and pain, but the evidence so far from controlled trials for such a relationship, other than in osteomalacia, is unconvincing.
Is there an answer to this question: What did an analysis of the 13 studies of pain treatment conclude about the effect of real treament versus sham treatments?

Answer: little difference in the effect


Question: Greek vocal music extends far back into ancient times where mixed-gender choruses performed for entertainment, celebration and spiritual reasons. Instruments during that period included the double-reed aulos and the plucked string instrument, the lyre, especially the special kind called a kithara. Music played an important role in the education system during ancient times. Boys were taught music from the age of six. Later influences from the Roman Empire, Middle East, and the Byzantine Empire also had effect on Greek music.
Is there an answer to this question: Greek vocal music goes back how far in history?

Answer:
ancient times