In this task, you are given a question and a context passage. You have to answer the question based on the given passage.

Q: What determines the model of forces?, Context: For certain physical scenarios, it is impossible to model forces as being due to gradient of potentials. This is often due to macrophysical considerations that yield forces as arising from a macroscopic statistical average of microstates. For example, friction is caused by the gradients of numerous electrostatic potentials between the atoms, but manifests as a force model that is independent of any macroscale position vector. Nonconservative forces other than friction include other contact forces, tension, compression, and drag. However, for any sufficiently detailed description, all these forces are the results of conservative ones since each of these macroscopic forces are the net results of the gradients of microscopic potentials.

A: gradient of potentials
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Q: What did Kerry later run for?, Context: The junior U.S. Senator from Massachusetts, Paul Tsongas, announced in 1984 that he would be stepping down for health reasons. Kerry ran, and as in his 1982 race for Lieutenant Governor, he did not receive the endorsement of the party regulars at the state Democratic convention. Congressman James Shannon, a favorite of House Speaker Tip O'Neill, was the early favorite to win the nomination, and he "won broad establishment support and led in early polling." Again as in 1982, however, Kerry prevailed in a close primary.

A: Senator
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Q: Where did Hayek relocate after his retirement?, Context: From 1962 until his retirement in 1968, he was a professor at the University of Freiburg, West Germany, where he began work on his next book, Law, Legislation and Liberty. Hayek regarded his years at Freiburg as "very fruitful". Following his retirement, Hayek spent a year as a visiting professor of philosophy at the University of California, Los Angeles, where he continued work on Law, Legislation and Liberty, teaching a graduate seminar by the same name and another on the philosophy of social science. Primary drafts of the book were completed by 1970, but Hayek chose to rework his drafts and finally brought the book to publication in three volumes in 1973, 1976 and 1979.

A:
California
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