Who among the four rightly guided caliphs introduced the systems of Bayr at māl?

Explanation

Bayt al-mal ( ﺑﻴﺖ ﺍﻟﻤﺎﻝ ) is an Arabic term that is translated as "House of money" or "House of Wealth." Historically, it was a financial institution responsible for the administration of taxes in Islamic states , particularly in the early Islamic Caliphate . It served as a royal treasury for the caliphs and sultans , managing personal finances and government expenditures. Further, it administered distributions of zakat revenues for public works.