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: Who ultimately got West a record deal?, Context: According to Capitol Record's A&R, Joe Weinberger, he was approached by West and almost signed a deal with him, but another person in the company convinced Capitol's president not to. Desperate to keep West from defecting to another label, then-label head Damon Dash reluctantly signed West to Roc-A-Fella Records. Jay-Z later admitted that Roc-A-Fella was initially reluctant to support West as a rapper, claiming that many saw him as a producer first and foremost, and that his background contrasted with that of his labelmates.

A: Damon Dash
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Q: How large is the IAH airport?, Context: The primary city airport is George Bush Intercontinental Airport (IAH), the tenth-busiest in the United States for total passengers, and twenty eighth-busiest worldwide. Bush Intercontinental currently ranks fourth in the United States for non-stop domestic and international service with 182 destinations. In 2006, the United States Department of Transportation named IAH the fastest-growing of the top ten airports in the United States. The Houston Air Route Traffic Control Center stands on the George Bush Intercontinental Airport grounds.

A:
twenty eighth-busiest worldwide
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