How were the elevations of the Himalayas surveyed in the mid-nineteenth century? How were the errors in Everest's survey data interpreted by John Pratt and George Airy?
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A telescope, mounted on a table tangential and perpendicular to Earth's center, is sighted on the North Star. This star is nearly directly above our rotational axis. The angle between the line drawn to the North Star and the line to the center of Earth determines latitude. However, this only works when Earth is uniform and the surface smooth. Large masses of rock pull the plumb bob towards them and away from the center of Earth, causing error, although calculated error was much greater than the observed error. Pratt proposed that the deflection is consistent with observations because the crust below the mountains is of lower density. Airy suggested that the crust was more dense than expected, providing a root below the mountain.
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When it is summer in the Northern Hemisphere, Earth is tilted
A. so that the North Pole tilts away from the Sun. B. so that the North Pole tilts toward the Sun. C. so that the South Pole tilts toward the Sun. D. so that the North Pole and South Pole are equidistant from the Sun.
Distinguish between MRFs, mixed-waste processing, and single-stream recycling
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The original Clean Air Act was designed to reduce lead emissions, and the 1990 Clean Air Act amendments were designed to reduce urban smog. As implied by the graph's data, one unintended consequence of the legislation and its amendments was _________.
a. an increase in the nontransportation uses of lead b. an increased use of MTBE c. an increase in water pollution d. a return to the use of leaded gasoline for improved combustion
A ___________ pesticide does not degrade after being sprayed and remains in the environment for years causing long-term problems.
Fill in the blank(s) with the appropriate word(s).