80. Solving a chemistry problem

63. A weighing of 0.6000 g of sodium hydroxide contaminated with Na2CO3 and indifferent impurities was dissolved in 100.0 ml of water. An aliquot of 10.00 ml was titrated with 0.05220 M H2SO4 solution. In the presence of phenolphthalein, 11.89 ml of titrant was consumed, and in the presence of methyl orange, 12.79 ml. Calculate the mass fractions of NaOH and Na2CO3 in the analyzed sample.