Infrared spectra are customarily recorded on a transmittance scale so that weak and strong bands can be displayed on the same scale. The region near 2 000 cm^-1 in the infrared spectra of compounds A and B is shown in the figure. Note that absorption corresponds to a downward peak on this scale. The spectra were recorded from a 0.010 0 M solution of each, in cells with 0.005 00-cm pathlengths. A mixture of A and B in a 0.005 00-cm cell gave a transmittance of 34.0% at 2 022 cm^-1 and 38.3% at 1 993 cm^-1. Find the concentrations of A and B.

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100 80 60 A 40 B 2 022 20 cm-1 1 993 cm-1 2 100 2 000 1 900 Wavenumber (cm) Wavenumber Pure A Pure B 2 022 cm-1 31.0% T 97.4% T 1 993 cm-1 79.7% T 20.0% T Transmittance (%)