Context and question: During the Cenozoic era, specifically about 25 million years ago during the Miocene and Pliocene epochs, the continental climate became favorable to the evolution of grasslands. Existing forest biomes declined and grasslands became much more widespread. The grasslands provided a new niche for mammals, including many ungulates and glires, that switched from browsing diets to grazing diets. Traditionally, the spread of grasslands and the development of grazers have been strongly linked. However, an examination of mammalian teeth suggests that it is the open, gritty habitat and not the grass itself which is linked to diet changes in mammals, giving rise to the "grit, not grass" hypothesis.
When did the Cenozoic era end?
Answer: unanswerable
Context and question: In the Age of Reason philosophical tracts and speculations on history and human nature integrated literature with social and political developments. The inevitable reaction was the explosion of Romanticism in the later 18th century which reclaimed the imaginative and fantastical bias of old romances and folk-literature and asserted the primacy of individual experience and emotion. But as the 19th-century went on, European fiction evolved towards realism and naturalism, the meticulous documentation of real life and social trends. Much of the output of naturalism was implicitly polemical, and influenced social and political change, but 20th century fiction and drama moved back towards the subjective, emphasising unconscious motivations and social and environmental pressures on the individual. Writers such as Proust, Eliot, Joyce, Kafka and Pirandello exemplify the trend of documenting internal rather than external realities.
What was the reaction to the Age of Reason in the later 19th century?
Answer: unanswerable
Context and question: According to reciprocity, the efficiency of an antenna used as a receiving antenna is identical to the efficiency as defined above. The power that an antenna will deliver to a receiver (with a proper impedance match) is reduced by the same amount. In some receiving applications, the very inefficient antennas may have little impact on performance. At low frequencies, for example, atmospheric or man-made noise can mask antenna inefficiency. For example, CCIR Rep. 258-3 indicates man-made noise in a residential setting at 40 MHz is about 28 dB above the thermal noise floor. Consequently, an antenna with a 20 dB loss (due to inefficiency) would have little impact on system noise performance. The loss within the antenna will affect the intended signal and the noise/interference identically, leading to no reduction in signal to noise ratio (SNR).
At lesser frequencies what can account for incorrect assumptions about efficiency?
Answer:
man-made noise