based on your knowledge, why are partisanship and a two-party system significant parts of US politics

Partisanship causes survey respondents to answer political surveys differently, even if the survey asks a question with an objective answer. People with strong partisan beliefs are 12% more likely to give an incorrect answer that benefits their preferred party than an incorrect answer that benefits another party.

- three-quarters or two-thirds..

- "the constitution provides that an amendment may be proposed either by the congress with a two-thirds majority vote in both the house of representatives and the senate or by a constitutional convention called for by two-thirds of the state legislatures."

< 3

first second and third

explanation: