Problem: Antenna (radio):

Polarization is predictable from an antenna's geometry, although in some cases it is not at all obvious (such as for the quad antenna). An antenna's linear polarization is generally along the direction (as viewed from the receiving location) of the antenna's currents when such a direction can be defined. For instance, a vertical whip antenna or Wi-Fi antenna vertically oriented will transmit and receive in the vertical polarization. Antennas with horizontal elements, such as most rooftop TV antennas in the United States, are horizontally polarized (broadcast TV in the U.S. usually uses horizontal polarization). Even when the antenna system has a vertical orientation, such as an array of horizontal dipole antennas, the polarization is in the horizontal direction corresponding to the current flow. The polarization of a commercial antenna is an essential specification.

What is a more complicated type of polarization from an antenna's geometry?
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A: quad antenna

Problem: Group (mathematics):

The concept of a group arose from the study of polynomial equations, starting with Evariste Galois in the 1830s. After contributions from other fields such as number theory and geometry, the group notion was generalized and firmly established around 1870. Modern group theoryan active mathematical disciplinestudies groups in their own right.a["] To explore groups, mathematicians have devised various notions to break groups into smaller, better-understandable pieces, such as subgroups, quotient groups and simple groups. In addition to their abstract properties, group theorists also study the different ways in which a group can be expressed concretely (its group representations), both from a theoretical and a computational point of view. A theory has been developed for finite groups, which culminated with the classification of finite simple groups announced in 1983.aa["] Since the mid-1980s, geometric group theory, which studies finitely generated groups as geometric objects, has become a particularly active area in group theory.

When did theorists begin exploring the theoretical and computational point of view?
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A: unanswerable

Problem: Antarctica:

Africa separated from Antarctica in the Jurassic, around 160 Ma, followed by the Indian subcontinent in the early Cretaceous (about 125 Ma). By the end of the Cretaceous, about 66 Ma, Antarctica (then connected to Australia) still had a subtropical climate and flora, complete with a marsupial fauna. In the Eocene epoch, about 40 Ma Australia-New Guinea separated from Antarctica, so that latitudinal currents could isolate Antarctica from Australia, and the first ice began to appear. During the EoceneOligocene extinction event about 34 million years ago, CO2 levels have been found to be about 760 ppm and had been decreasing from earlier levels in the thousands of ppm.

When did Antarctica have a tropical cimate?
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A: unanswerable

Problem: Beyonce:

Her first acting role of 2006 was in the comedy film The Pink Panther starring opposite Steve Martin, grossing $158.8 million at the box office worldwide. Her second film Dreamgirls, the film version of the 1981 Broadway musical loosely based on The Supremes, received acclaim from critics and grossed $154 million internationally. In it, she starred opposite Jennifer Hudson, Jamie Foxx, and Eddie Murphy playing a pop singer based on Diana Ross. To promote the film, Beyonce released "Listen" as the lead single from the soundtrack album. In April 2007, Beyonce embarked on The Beyonce Experience, her first worldwide concert tour, visiting 97 venues and grossed over $24 million.[note 1] Beyonce conducted pre-concert food donation drives during six major stops in conjunction with her pastor at St. John's and America's Second Harvest. At the same time, B'Day was re-released with five additional songs, including her duet with Shakira "Beautiful Liar".

Beyonce's first world tour was when?
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A:
2007