Here is a question about this article: Predators are often another organism's prey, and likewise prey are often predators. Though blue jays prey on insects, they may in turn be prey for cats and snakes, and snakes may be the prey of hawks. One way of classifying predators is by trophic level. Organisms that feed on autotrophs, the producers of the trophic pyramid, are known as herbivores or primary consumers; those that feed on heterotrophs such as animals are known as secondary consumers. Secondary consumers are a type of carnivore, but there are also tertiary consumers eating these carnivores, quartary consumers eating them, and so forth. Because only a fraction of energy is passed on to the next level, this hierarchy of predation must end somewhere, and very seldom goes higher than five or six levels, and may go only as high as three trophic levels (for example, a lion that preys upon large herbivores such as wildebeest, which in turn eat grasses). A predator at the top of any food chain (that is, one that is preyed upon by no organism) is called an apex predator; examples include the orca, sperm whale, anaconda, Komodo dragon, tiger, lion, tiger shark, Nile crocodile, and most eagles and owls—and even omnivorous humans and grizzly bears. An apex predator in one environment may not retain this position as a top predator if introduced to another habitat, such as a dog among alligators, a skunk in the presence of the great horned owl immune to skunk spray, or a snapping turtle among jaguars; a predatory species introduced into an area where it faces no predators, such as a domestic cat or a dog in some insular environments, can become an apex predator by default.
What is the answer to this question: What limits the size of a trophic pyramid? 
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So... energy


Here is a question about this article: Video output connections varied from one model of the console to the next. The original HVC-001 model of the Family Computer featured only radio frequency (RF) modulator output. When the console was released in North America and Europe, support for composite video through RCA connectors was added in addition to the RF modulator. The HVC-101 model of the Famicom dropped the RF modulator entirely and adopted composite video output via a proprietary 12-pin "multi-out" connector first introduced for the Super Famicom/Super Nintendo Entertainment System. Conversely, the North American re-released NES-101 model most closely resembled the original HVC-001 model Famicom, in that it featured RF modulator output only. Finally, the PlayChoice-10 utilized an inverted RGB video output.
What is the answer to this question: The re-released NES-101 model in North America went back to what perceived primitive output?
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So... RF modulator


Here is a question about this article: 1762 brought two new countries into the war. Britain declared war against Spain on 4 January 1762; Spain reacted by issuing their own declaration of war against Britain on 18 January. Portugal followed by joining the war on Britain's side. Spain, aided by the French, launched an invasion of Portugal and succeeded in capturing Almeida. The arrival of British reinforcements stalled a further Spanish advance, and the Battle of Valencia de Alcántara saw British-Portuguese forces overrun a major Spanish supply base. The invaders were stopped on the heights in front of Abrantes (called the pass to Lisbon) where the Anglo-Portuguese were entrenched. Eventually the Anglo-Portuguese army, aided by guerrillas and practicing a scorched earth strategy, chased the greatly reduced Franco-Spanish army back to Spain, recovering almost all the lost towns, among them the Spanish headquarters in Castelo Branco full of wounded and sick that had been left behind.
What is the answer to this question: Identify a new country that joined the war in 1762?
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So...
Spain