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Figure 7a

Figure 7a: Fast Fourier transform display of the native version of the 16 kHz / 16-bit
multiple sine wave signal.

Fast Fourier transform display of the native version of the 16 kHz / 16-bit multiple sine wave signal. Frequency is on the horizontal axis from 0 to 10.00 kHz, and amplitude is on the vertical axis. The multiple sine waves are represented in frequency as high-amplitude spikes at the locations of the four sine wave signals: 500 Hz, 1400 Hz, 2600 Hz, and 3400 Hz. There is no other high-amplitude information.