Problem: Matter should not be confused with mass, as the two are not quite the same in modern physics. For example, mass is a conserved quantity, which means that its value is unchanging through time, within closed systems. However, matter is not conserved in such systems, although this is not obvious in ordinary conditions on Earth, where matter is approximately conserved. Still, special relativity shows that matter may disappear by conversion into energy, even inside closed systems, and it can also be created from energy, within such systems. However, because mass (like energy) can neither be created nor destroyed, the quantity of mass and the quantity of energy remain the same during a transformation of matter (which represents a certain amount of energy) into non-material (i.e., non-matter) energy. This is also true in the reverse transformation of energy into matter.
What can be created or destroyed?
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Answer: unanswerable

Problem: The semi-arid high plains in the state's northwestern corner harbor few natural forests; the region has a rolling to flat landscape with intermittent canyons and mesa ranges like the Glass Mountains. Partial plains interrupted by small, sky island mountain ranges like the Antelope Hills and the Wichita Mountains dot southwestern Oklahoma; transitional prairie and oak savannahs cover the central portion of the state. The Ozark and Ouachita Mountains rise from west to east over the state's eastern third, gradually increasing in elevation in an eastward direction.
In which direction do the Ozark mountains get higher?
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Answer: eastward

Problem: One person may presume knowledge of another person's sexual orientation based upon perceived characteristics, such as appearance, clothing, tone of voice, and accompaniment by and behavior with other people. The attempt to detect sexual orientation in social situations is known as gaydar; some studies have found that guesses based on face photos perform better than chance. 2015 research suggests that "gaydar" is an alternate label for using LGBT stereotypes to infer orientation, and that face-shape is not an accurate indication of orientation.
What is a term for someone who tries to determine someones sexuality?
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Answer:
gaydar