There are problems with the first sentence, and it's not really needed when
working with this question. So let's just take the 20 (Hz ?) frequency from
the first sentence, and ignore the rest of it for right now.
Wavelength = (speed) / (frequency) =
(331 m/s) / (20 Hz) = <em>16.55 meters</em>.
<span>Self-dispatch to another incident</span>
Statement :- We assume the orthagonal sequence 
in Hilbert space, now 
, the Fourier coefficients are given by:
Then Bessel's inequality give us:
Proof :- We assume the following equation is true
So that, 
is projection of 
onto the surface by the first 
of the 
. For any event, 
Now, by Pythagoras theorem:
Now, we can deduce that from the above equation that;
For 
, we have
Hence, Proved
You have to find the calculate<span> the circumference first then you can just multiply the diameter by π, which is about 3.142. That gives you the distance for each </span>revolution<span>. Then you can multiply by the </span>number of revolutions<span> per minute.
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