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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1 Stain removal varies according to type and size of stain, but can run an additional .10 cents per square foot, or $30 for 300-square feet of cleaning space. 2  Deodorizing averages .05 cents per square foot, or $15 for 300-square feet of cleaning area.3  Each carpet cleaning company has an individual furniture moving policy. Staircase cleaning runs about $2-$3 each stair. 2  Stain removal varies according to type and size of stain, but can run an additional .10 cents per square foot, or $30 for 300-square feet of cleaning space.