An agreed set of regulations, conventions and customs by which a country or an organisation is governed is the ________

The answer is "constitution". A constitution is a set of rules and principles that govern a country or an organization. It serves as a framework for how the government operates, how power is divided and shared, and what rights and freedoms are guaranteed to the citizens or members. Constitutions typically outline the structure and powers of the government, the rights and responsibilities of individuals, and the procedures for making and enforcing laws. They are usually written documents that are considered to be the supreme law of the land, meaning that all other laws and regulations must be in compliance with the constitution. In summary, a constitution is a crucial document that outlines how a country or organization is governed, and it helps to ensure that the government operates fairly and in accordance with the rule of law.