Given a scientific question, generate a correct answer to it.

[Q]: What has traditionally been defined as a force of attraction between two masses?
[A]: gravity

[Q]: In addition to insects, what large invertebrate phylum includes animals such as spiders, centipedes, and lobsters?
[A]: arthropoda

[Q]: What is the purpose of utilizing careful farming practices such as rotating crops or planting nutrient rich crops?
[A]:
improve soil quality