One way to determine sulfur is by combustion analysis. This procedure produces a mixture of SO2 and SO3 that can be passed through H2O2 to convert both into H2SO4, which is titrated with standard base. When 6.123 mg of a substance were burned, the H2SO4 required 3.01 mL of 0.015 76 M NaOH for titration. Find the weight percent of sulfur in the sample.