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

Ex Input:
What has to be done with lights in order for them to work?, Context: Entry lights can be used outside to illuminate and signal the entrance to a property. These lights are installed for safety, security, and for decoration.

Ex Output:
installed

Ex Input:
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.

Ex Output:
gradient of potentials

Ex Input:
The authority that does not exist is in the churches is referred to as what else?, Context: Various ecumenical movements have attempted cooperation or reorganization of the various divided Protestant denominations, according to various models of union, but divisions continue to outpace unions, as there is no overarching authority to which any of the churches owe allegiance, which can authoritatively define the faith. Most denominations share common beliefs in the major aspects of the Christian faith while differing in many secondary doctrines, although what is major and what is secondary is a matter of idiosyncratic belief.

Ex Output:
overarching authority