The problem: Answer a question about this article:
In December, Beyonce along with a variety of other celebrities teamed up and produced a video campaign for "Demand A Plan", a bipartisan effort by a group of 950 US mayors and others designed to influence the federal government into rethinking its gun control laws, following the Sandy Hook Elementary School shooting. Beyonce became an ambassador for the 2012 World Humanitarian Day campaign donating her song "I Was Here" and its music video, shot in the UN, to the campaign. In 2013, it was announced that Beyonce would work with Salma Hayek and Frida Giannini on a Gucci "Chime for Change" campaign that aims to spread female empowerment. The campaign, which aired on February 28, was set to her new music. A concert for the cause took place on June 1, 2013 in London and included other acts like Ellie Goulding, Florence and the Machine, and Rita Ora. In advance of the concert, she appeared in a campaign video released on 15 May 2013, where she, along with Cameron Diaz, John Legend and Kylie Minogue, described inspiration from their mothers, while a number of other artists celebrated personal inspiration from other women, leading to a call for submission of photos of women of viewers' inspiration from which a selection was shown at the concert. Beyonce said about her mother Tina Knowles that her gift was "finding the best qualities in every human being." With help of the crowdfunding platform Catapult, visitors of the concert could choose between several projects promoting education of women and girls. Beyonce is also taking part in "Miss a Meal", a food-donation campaign, and supporting Goodwill charity through online charity auctions at Charitybuzz that support job creation throughout Europe and the U.S.
The Demand a Plan video campaign followed what tragic event?
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The answer: Sandy Hook Elementary School shooting.

The problem: Answer a question about this article:
along with two inequality systems expressing economic efficiency. In this model, the (transposed) probability vector p represents the prices of the goods while the probability vector q represents the "intensity" at which the production process would run. The unique solution represents the growth factor which is 1 plus the rate of growth of the economy; the rate of growth equals the interest rate. Proving the existence of a positive growth rate and proving that the growth rate equals the interest rate were remarkable achievements, even for von Neumann.
What is the rate of qrowth equal to?
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The answer: rate of growth equals the interest rate

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The two nations planned a joint mission to dock the last US Apollo craft with a Soyuz, known as the Apollo-Soyuz Test Project (ASTP). To prepare, the US designed a docking module for the Apollo that was compatible with the Soviet docking system, which allowed any of their craft to dock with any other (e.g. Soyuz/Soyuz as well as Soyuz/Salyut). The module was also necessary as an airlock to allow the men to visit each other's craft, which had incompatible cabin atmospheres. The USSR used the Soyuz 16 mission in December 1974 to prepare for ASTP.
ASTP stands for what?
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The answer: Apollo-Soyuz Test Project

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With the Conference of Berlin of 1884, Portuguese Africa territories had their borders formally established on request of Portugal in order to protect the centuries-long Portuguese interests in the continent from rivalries enticed by the Scramble for Africa. Portuguese Africa's cities and towns like Nova Lisboa, Sa da Bandeira, Silva Porto, Malanje, Tete, Vila Junqueiro, Vila Pery and Vila Cabral were founded or redeveloped inland during this period and beyond. New coastal towns like Beira, Mocamedes, Lobito, Joao Belo, Nacala and Porto Amelia were also founded. Even before the turn of the 20th century, railway tracks as the Benguela railway in Angola, and the Beira railway in Mozambique, started to be built to link coastal areas and selected inland regions.
When were railroad tracks being installed Portugese Africa?
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The answer:
before the turn of the 20th century