Problem: Capacitor:

Ripple current is the AC component of an applied source (often a switched-mode power supply) whose frequency may be constant or varying. Ripple current causes heat to be generated within the capacitor due to the dielectric losses caused by the changing field strength together with the current flow across the slightly resistive supply lines or the electrolyte in the capacitor. The equivalent series resistance (ESR) is the amount of internal series resistance one would add to a perfect capacitor to model this. Some types of capacitors, primarily tantalum and aluminum electrolytic capacitors, as well as some film capacitors have a specified rating value for maximum ripple current.

What name is given to the AC component of an applied source having either constant or alternating frequency?
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A: Ripple current

Problem: Antarctica:

As a result of continued warming, the polar ice caps melted and much of Gondwana became a desert. In Eastern Antarctica, seed ferns or pteridosperms became abundant and large amounts of sandstone and shale were laid down at this time. Synapsids, commonly known as "mammal-like reptiles", were common in Antarctica during the Early Triassic and included forms such as Lystrosaurus. The Antarctic Peninsula began to form during the Jurassic period (206146 Ma), and islands gradually rose out of the ocean. Ginkgo trees, conifers, bennettites, horsetails, ferns and cycads were plentiful during this period. In West Antarctica, coniferous forests dominated through the entire Cretaceous period (14666 Ma), though southern beech became more prominent towards the end of this period. Ammonites were common in the seas around Antarctica, and dinosaurs were also present, though only three Antarctic dinosaur genera (Cryolophosaurus and Glacialisaurus, from the Hanson Formation, and Antarctopelta) have been described to date. It was during this era that Gondwana began to break up.

What began to form during the years 204-166 Ma?
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A: unanswerable

Problem: Greece:

Following the Fourth Crusade and the fall of Constantinople to the "Latins" in 1204 mainland Greece was split between the Greek Despotate of Epirus (a Byzantine successor state) and Frankish rule (known as the Frankokratia), while some islands came under Venetian rule. The re-establishment of the Byzantine imperial capital in Constantinople in 1261 was accompanied by the empire's recovery of much of the Greek peninsula, although the Frankish Principality of Achaea in the Peloponnese and the rival Greek Despotate of Epirus in the north both remained important regional powers into the 14th century, while the islands remained largely under Genoese and Venetian control.

The Grecian islands in the 14th century were under the control of who?
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A: Genoese and Venetian

Problem: Hard rock:

In the early 1970s the Rolling Stones developed their hard rock sound with Exile on Main St. (1972). Initially receiving mixed reviews, according to critic Steve Erlewine it is now "generally regarded as the Rolling Stones' finest album". They continued to pursue the riff-heavy sound on albums including It's Only Rock 'n' Roll (1974) and Black and Blue (1976). Led Zeppelin began to mix elements of world and folk music into their hard rock from Led Zeppelin III (1970) and Led Zeppelin IV (1971). The latter included the track "Stairway to Heaven", which would become the most played song in the history of album-oriented radio. Deep Purple continued to define hard rock, particularly with their album Machine Head (1972), which included the tracks "Highway Star" and "Smoke on the Water". In 1975 guitarist Ritchie Blackmore left, going on to form Rainbow and after the break-up of the band the next year, vocalist David Coverdale formed Whitesnake. 1970 saw The Who release Live at Leeds, often seen as the archetypal hard rock live album, and the following year they released their highly acclaimed album Who's Next, which mixed heavy rock with extensive use of synthesizers. Subsequent albums, including Quadrophenia (1973), built on this sound before Who Are You (1978), their last album before the death of pioneering rock drummer Keith Moon later that year.

What two hard rock songs are featured on Deep Purple's Machine Head album?
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A:
"Highway Star" and "Smoke on the Water"