A manganese complex formed from a solution containing potassium bromide and oxalate ion is purified and analyzed. It contains 10.0% Mn 28.6%, potassium 8.8%, carbon, and 29.2% bromine by mass. The remainder of the compound is oxygen. An aqueous solution of the complex has about the same electrical conductivity as an equimolar solution of K4[Fe(CN)6]. Write the formula of the compound, using brackets to denote the manganese and its coordination sphere.