95. Solving a chemistry problem

5. The chromatogram shows peaks of 1-ethyl-2-methylbenzene, 1-isopropyl-3-methylbenzene, o-xylene, and cumene. The peak heights are 253, 27, 128, and 58 mm, respectively, the peak widths at half height are 2.4, 5.8, 2.7, and 4.9 mm, respectively. Calculate the percentage of the mixture components, taking into account that the peak shape is close to the normal distribution curve.