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

[EX Q]: Frank Sinatra is an example of what genre of singer?, Context: Artists contributing to this format include mainly soft rock/pop singers such as, Andy Williams, Johnny Mathis, Nana Mouskouri, Celine Dion, Julio Iglesias, Frank Sinatra, Barry Manilow, Engelbert Humperdinck, and Marc Anthony.
[EX A]: pop

[EX 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.
[EX A]: gradient of potentials

[EX Q]: What quality should administrators seek in teachers?, Context: Since teachers can affect how students perceive the course materials, it has been found that teachers who showed enthusiasm towards the course materials and students can affect a positive learning experience towards the course materials. On teacher/course evaluations, it was found that teachers who have a positive disposition towards the course content tend to transfer their passion to receptive students. These teachers do not teach by rote but attempt to find new invigoration for the course materials on a daily basis. One of the difficulties in this approach is that teachers may have repeatedly covered a curriculum until they begin to feel bored with the subject which in turn bores the students as well. Students who had enthusiastic teachers tend to rate them higher than teachers who didn't show much enthusiasm for the course materials.
[EX A]:
enthusiasm