Rules that must be followed when using set operators in a query include:i$.$ The number of columns in both tables needs to be equal.ii$.$ The columns from each table that we want to combine do not require compatible datatypes.iii. We can only apply the ORDER BY clause to the combined table and not to the individual tables.iv$.$ The GROUP BY clause can only be applied to the individual tables $($i$.$e$.$ before the UNION operation$)$ and not the combined result.All of the aboveiii,ivii,iiii,iii,iv