The only bird known to make use of infrasound (at about 20 Hz) is the western capercaillie. The hearing range of birds is from below 50 Hz (infrasound) to around 12 kHz, with maximum sensitivity between 1 and 5 kHz. The range of frequencies at which birds call in an environment varies with the quality of habitat and the ambient sounds.
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Still, the price range of some of the commercial carpet cleaning companies varies at around $0.15 to $0.20 per square foot depending on the area and cleaning method. For tougher stains, there may be an extra charge between $40-$50 for the job to be completed.