Here is a question about this article: Mechanically controlled variable capacitors allow the plate spacing to be adjusted, for example by rotating or sliding a set of movable plates into alignment with a set of stationary plates. Low cost variable capacitors squeeze together alternating layers of aluminum and plastic with a screw. Electrical control of capacitance is achievable with varactors (or varicaps), which are reverse-biased semiconductor diodes whose depletion region width varies with applied voltage. They are used in phase-locked loops, amongst other applications.
What is the answer to this question: What is an application of varactors?
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So... phase-locked loops


Here is a question about this article: At the Battle of Mars-la-Tours, the Prussian 12th Cavalry Brigade, commanded by General Adalbert von Bredow, conducted a charge against a French artillery battery. The attack was a costly success and came to be known as "von Bredow's Death Ride", which was held to prove that cavalry charges could still prevail on the battlefield. Use of traditional cavalry on the battlefields of 1914 proved to be disastrous, due to accurate, long-range rifle fire, machine-guns and artillery. Von Bredow's attack had succeeded only because of an unusually effective artillery bombardment just before the charge, along with favorable terrain that masked his approach.
What is the answer to this question: What was one of two factors that led von Bredow's narrow success on the battlefield?
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So... favorable terrain that masked his approach


Here is a question about this article: The myth of a Trojan founding with Greek influence was reconciled through an elaborate genealogy (the Latin kings of Alba Longa) with the well-known legend of Rome's founding by Romulus and Remus. The most common version of the twins' story displays several aspects of hero myth. Their mother, Rhea Silvia, had been ordered by her uncle the king to remain a virgin, in order to preserve the throne he had usurped from her father. Through divine intervention, the rightful line was restored when Rhea Silvia was impregnated by the god Mars. She gave birth to twins, who were duly exposed by order of the king but saved through a series of miraculous events.
What is the answer to this question: What type of events saved the twins of Roman myth?
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So...
miraculous