Problem: Capacitors are connected in parallel with the power circuits of most electronic devices and larger systems (such as factories) to shunt away and conceal current fluctuations from the primary power source to provide a "clean" power supply for signal or control circuits. Audio equipment, for example, uses several capacitors in this way, to shunt away power line hum before it gets into the signal circuitry. The capacitors act as a local reserve for the DC power source, and bypass AC currents from the power supply. This is used in car audio applications, when a stiffening capacitor compensates for the inductance and resistance of the leads to the lead-acid car battery.
What do parallel capacitors do to fluctuating current in order to deliver "dirty" power for control circuits?
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Answer: unanswerable

Problem: Plant circadian rhythms tell the plant what season it is and when to flower for the best chance of attracting pollinators. Behaviors showing rhythms include leaf movement, growth, germination, stomatal/gas exchange, enzyme activity, photosynthetic activity, and fragrance emission, among others. Circadian rhythms occur as a plant entrains to synchronize with the light cycle of its surrounding environment. These rhythms are endogenously generated and self-sustaining and are relatively constant over a range of ambient temperatures. Important features include two interacting transcription-translation feedback loops: proteins containing PAS domains, which facilitate protein-protein interactions; and several photoreceptors that fine-tune the clock to different light conditions. Anticipation of changes in the environment allows appropriate changes in a plant's physiological state, conferring an adaptive advantage. A better understanding of plant circadian rhythms has applications in agriculture, such as helping farmers stagger crop harvests to extend crop availability and securing against massive losses due to weather.
Where can an understanding of circadian rhythms of plants be an advantage?
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Answer: agriculture

Problem: Under the Capetian dynasty France slowly began to expand its authority over the nobility, growing out of the Ile-de-France to exert control over more of the country in the 11th and 12th centuries. They faced a powerful rival in the Dukes of Normandy, who in 1066 under William the Conqueror (duke 10351087), conquered England (r. 106687) and created a cross-channel empire that lasted, in various forms, throughout the rest of the Middle Ages. Normans also settled in Sicily and southern Italy, when Robert Guiscard (d. 1085) landed there in 1059 and established a duchy that later became the Kingdom of Sicily. Under the Angevin dynasty of Henry II (r. 115489) and his son Richard I (r. 118999), the kings of England ruled over England and large areas of France,[W] brought to the family by Henry II's marriage to Eleanor of Aquitaine (d. 1204), heiress to much of southern France.[X] Richard's younger brother John (r. 11991216) lost Normandy and the rest of the northern French possessions in 1204 to the French King Philip II Augustus (r. 11801223). This led to dissension among the English nobility, while John's financial exactions to pay for his unsuccessful attempts to regain Normandy led in 1215 to Magna Carta, a charter that confirmed the rights and privileges of free men in England. Under Henry III (r. 121672), John's son, further concessions were made to the nobility, and royal power was diminished. The French monarchy continued to make gains against the nobility during the late 12th and 13th centuries, bringing more territories within the kingdom under their personal rule and centralising the royal administration. Under Louis IX (r. 122670), royal prestige rose to new heights as Louis served as a mediator for most of Europe.[Y]
To what dynasty did Henry II belong?
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Answer:
Angevin