Which reform measure could voters use if they wanted to change a law about taxes?

The reform measure that voters could use if they wanted to change a law about taxes would be "initiative measures".

An Initiative is the process that enables citizens to place proposed statues and reforms on the voting ballots. In simple words, It's used to change or alter laws that are already in place.

the answer would be logic.

explanation:

an oligopoly is a term used to clarify the structure of a particular market, industry, or organization. a market is considered oligopolistic or amazingly focused when it is shared between a few companies.