Problem: The "photoelectrons" emitted as a result of the photoelectric effect have a certain kinetic energy, which can be measured. This kinetic energy (for each photoelectron) is independent of the intensity of the light, but depends linearly on the frequency; and if the frequency is too low (corresponding to a photon energy that is less than the work function of the material), no photoelectrons are emitted at all, unless a plurality of photons, whose energetic sum is greater than the energy of the photoelectrons, acts virtually simultaneously (multiphoton effect)  Assuming the frequency is high enough to cause the photoelectric effect, a rise in intensity of the light source causes more photoelectrons to be emitted with the same kinetic energy, rather than the same number of photoelectrons to be emitted with higher kinetic energy.
What happens if the photoelectron's frequency is too low?
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Answer: no photoelectrons are emitted at all


Problem: In June 1990, The Times ceased its policy of using courtesy titles ("Mr", "Mrs", or "Miss" prefixes) for living persons before full names on first reference, but it continues to use them before surnames on subsequent references. The more formal style is now confined to the "Court and Social" page, though "Ms" is now acceptable in that section, as well as before surnames in news sections.
When The Times ceased its policy of using courtesy titles, it continued to use them for what kind of name on references after the first?
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Answer: surnames


Problem: The establishment of the Santa Hermandad in 1480, and of the Real Audiencia del Reino de Galicia in 1500—a tribunal and executive body directed by the Governor-Captain General as a direct representative of the King—implied initially the submission of the Kingdom to the Crown, after a century of unrest and fiscal insubordination. As a result, from 1480 to 1520 the Kingdom of Galicia contributed more than 10% of the total earnings of the Crown of Castille, including the Americas, well over its economic relevance. Like the rest of Spain, the 16th century was marked by population growth up to 1580, when the simultaneous wars with the Netherlands, France and England hampered Galicia's Atlantic commerce, which consisted mostly in the exportation of sardines, wood, and some cattle and wine.
In spite of these wars, which exports did Galicia's Atlantic trade consist of?
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Answer:
sardines, wood, and some cattle and wine