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Donald Wills Douglas, Sr. built a plant in 1922 at Clover Field (Santa Monica Airport) for the Douglas Aircraft Company. In 1924, four Douglas-built planes took off from Clover Field to attempt the first aerial circumnavigation of the world. Two planes made it back, after having covered 27,553 miles (44,342 km) in 175 days, and were greeted on their return September 23, 1924, by a crowd of 200,000 (generously estimated). The Douglas Company (later McDonnell Douglas) kept facilities in the city until the 1960s.
What did Clover Field built airplanes attempt the first of?
A: aerial circumnavigation of the world

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All the objects from everyday life that we can bump into, touch or squeeze are composed of atoms. This atomic matter is in turn made up of interacting subatomic particlesusually a nucleus of protons and neutrons, and a cloud of orbiting electrons. Typically, science considers these composite particles matter because they have both rest mass and volume. By contrast, massless particles, such as photons, are not considered matter, because they have neither rest mass nor volume. However, not all particles with rest mass have a classical volume, since fundamental particles such as quarks and leptons (sometimes equated with matter) are considered "point particles" with no effective size or volume. Nevertheless, quarks and leptons together make up "ordinary matter", and their interactions contribute to the effective volume of the composite particles that make up ordinary matter.
All particles with rest mass have what kind of volume?
A: unanswerable

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Symbiosis played a major role in the co-evolution of flowering plants and the animals that pollinate them. Many plants that are pollinated by insects, bats, or birds have highly specialized flowers modified to promote pollination by a specific pollinator that is also correspondingly adapted. The first flowering plants in the fossil record had relatively simple flowers. Adaptive speciation quickly gave rise to many diverse groups of plants, and, at the same time, corresponding speciation occurred in certain insect groups. Some groups of plants developed nectar and large sticky pollen, while insects evolved more specialized morphologies to access and collect these rich food sources. In some taxa of plants and insects the relationship has become dependent, where the plant species can only be pollinated by one species of insect.
What did bats develop to access and collect these rich food sources?
A: unanswerable

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The culture of Greece has evolved over thousands of years, beginning in Mycenaean Greece and continuing most notably into Classical Greece, through the influence of the Roman Empire and its Greek Eastern continuation, the Eastern Roman or Byzantine Empire. Other cultures and nations, such as the Latin and Frankish states, the Ottoman Empire, the Venetian Republic, the Genoese Republic, and the British Empire have also left their influence on modern Greek culture, although historians credit the Greek War of Independence with revitalising Greece and giving birth to a single, cohesive entity of its multi-faceted culture.
Where did Greece culture begin?
A:
Mycenaean Greece