Problem: Antenna (radio):

One example of omnidirectional antennas is the very common vertical antenna or whip antenna consisting of a metal rod (often, but not always, a quarter of a wavelength long). A dipole antenna is similar but consists of two such conductors extending in opposite directions, with a total length that is often, but not always, a half of a wavelength long. Dipoles are typically oriented horizontally in which case they are weakly directional: signals are reasonably well radiated toward or received from all directions with the exception of the direction along the conductor itself; this region is called the antenna blind cone or null.

What is meant by the area where signals cannot be accepted well along the conductor?
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A: null


Problem: Sino-Tibetan relations during the Ming dynasty:

Van Praag states that the Ming court established diplomatic delegations with Tibet merely to secure urgently needed horses. Wang and Nyima argue that these were not diplomatic delegations at all, that Tibetan areas were ruled by the Ming since Tibetan leaders were granted positions as Ming officials, that horses were collected from Tibet as a mandatory "corvée" tax, and therefore Tibetans were "undertaking domestic affairs, not foreign diplomacy". Sperling writes that the Ming simultaneously bought horses in the Kham region while fighting Tibetan tribes in Amdo and receiving Tibetan embassies in Nanjing. He also argues that the embassies of Tibetan lamas visiting the Ming court were for the most part efforts to promote commercial transactions between the lamas' large, wealthy entourage and Ming Chinese merchants and officials. Kolmaš writes that while the Ming maintained a laissez-faire policy towards Tibet and limited the numbers of the Tibetan retinues, the Tibetans sought to maintain a tributary relationship with the Ming because imperial patronage provided them with wealth and power. Laird writes that Tibetans eagerly sought Ming court invitations since the gifts the Tibetans received for bringing tribute were much greater in value than the latter. As for the Yongle Emperor's gifts to his Tibetan and Nepalese vassals such as silver wares, Buddha relics, utensils for Buddhist temples and religious ceremonies, and gowns and robes for monks, Tsai writes "in his effort to draw neighboring states to the Ming orbit so that he could bask in glory, the Yongle Emperor was quite willing to pay a small price". The Information Office of the State Council of the PRC lists the Tibetan tribute items as oxen, horses, camels, sheep, fur products, medical herbs, Tibetan incenses, thangkas (painted scrolls), and handicrafts; while the Ming awarded Tibetan tribute-bearers an equal value of gold, silver, satin and brocade, bolts of cloth, grains, and tea leaves. Silk workshops during the Ming also catered specifically to the Tibetan market with silk clothes and furnishings featuring Tibetan Buddhist iconography.

What shops were catered to the Tibetan market?
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A: Silk workshops


Problem: Dwight D. Eisenhower:

As the election approached, other prominent citizens and politicians from both parties urged Eisenhower to run for president. In January 1948, after learning of plans in New Hampshire to elect delegates supporting him for the forthcoming Republican National Convention, Eisenhower stated through the Army that he was "not available for and could not accept nomination to high political office"; "life-long professional soldiers", he wrote, "in the absence of some obvious and overriding reason, [should] abstain from seeking high political office". Eisenhower maintained no political party affiliation during this time. Many believed he was forgoing his only opportunity to be president; Republican Thomas E. Dewey was considered the other probable winner, would presumably serve two terms, and Eisenhower, at age 66 in 1956, would then be too old.

How old would Eisenhower be in 1956?
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A: 66


Problem: Red:

Red was the color of the banner of the Byzantine emperors. In Western Europe, Emperor Charlemagne painted his palace red as a very visible symbol of his authority, and wore red shoes at his coronation. Kings, princes and, beginning in 1295, Roman Catholic cardinals began to wear red costumes. When Abbe Suger rebuilt Saint Denis Basilica outside Paris in the early 12th century, he added stained glass windows colored blue cobalt glass and red glass tinted with copper. Together they flooded the basilica with a mystical light. Soon stained glass windows were being added to cathedrals all across France, England and Germany. In Medieval painting red was used to attract attention to the most important figures; both Christ and the Virgin Mary were commonly painted wearing red mantles.

Who rebuilt the basilica of Saint Denis?
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A:
Abbe Suger