The problem: Answer a question about this article:
Nonvascular land plants are embryophytes that lack the vascular tissues xylem and phloem. They include mosses, liverworts and hornworts. Pteridophytic vascular plants with true xylem and phloem that reproduced by spores germinating into free-living gametophytes evolved during the Silurian period and diversified into several lineages during the late Silurian and early Devonian. Representatives of the lycopods have survived to the present day. By the end of the Devonian period, several groups, including the lycopods, sphenophylls and progymnosperms, had independently evolved "megaspory" their spores were of two distinct sizes, larger megaspores and smaller microspores. Their reduced gametophytes developed from megaspores retained within the spore-producing organs (megasporangia) of the sporophyte, a condition known as endospory. Seeds consist of an endosporic megasporangium surrounded by one or two sheathing layers (integuments). The young sporophyte develops within the seed, which on germination splits to release it. The earliest known seed plants date from the latest Devonian Famennian stage. Following the evolution of the seed habit, seed plants diversified, giving rise to a number of now-extinct groups, including seed ferns, as well as the modern gymnosperms and angiosperms. Gymnosperms produce "naked seeds" not fully enclosed in an ovary; modern representatives include conifers, cycads, Ginkgo, and Gnetales. Angiosperms produce seeds enclosed in a structure such as a carpel or an ovary. Ongoing research on the molecular phylogenetics of living plants appears to show that the angiosperms are a sister clade to the gymnosperms.
What makes mosses different from other land plants?
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The answer: lack the vascular tissues

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Hunting and gathering was humanity's first and most successful adaptation, occupying at least 90 percent of human history. Following the invention of agriculture, hunter-gatherers have been displaced or conquered by farming or pastoralist groups in most parts of the world.
What are the basic types of agricultural groups?
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The answer: farming or pastoralist groups

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One recent proponent of the laws solution is Tim Maudlin who argues that the fundamental laws of physics are laws of temporal evolution (see Maudlin ). However, elsewhere Maudlin argues: "[the] passage of time is an intrinsic asymmetry in the temporal structure of the world... It is the asymmetry that grounds the distinction between sequences that runs from past to future and sequences which run from future to past" [ibid, 2010 edition, p. 108]. Thus it is arguably difficult to assess whether Maudlin is suggesting that the direction of time is a consequence of the laws or is itself primitive.
Who argues that the fundamental laws of physics are laws of temporal evolution?
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The answer: Tim Maudlin

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RCA 45s were also adapted to the smaller spindle of an LP player with a plastic snap-in insert known as a "spider". These inserts, commissioned by RCA president David Sarnoff and invented by Thomas Hutchison, were prevalent starting in the 1960s, selling in the tens of millions per year during the 45 rpm heyday. In countries outside the U.S., 45s often had the smaller album-sized holes, e.g., Australia and New Zealand, or as in the United Kingdom, especially before the 1970s, the disc had a small hole within a circular central section held only by three or four lands so that it could be easily punched out if desired (typically for use in jukeboxes).
How many spiders were sold in the 45 rpm heydays?
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The answer:
tens of millions per year