To develop this problem, it is necessary to apply the concepts related to Beat
The Beat is an acoustic phenomenon that is generated by two sine waves interfering with slightly different frequencies. The beat frequency is equal to the difference in the frequencies of the two original waves:

Our values are given as


For the particular case we have two possible frequencies:






Therefore the two possibles frequencies of the other players note are 437.9Hz and 442.1Hz
Answer:
The value is 
Explanation:
From the question we are told that
The volume of liquid nitrogen is 
The density of nitrogen at gaseous form is
= The dry air at sea level
Generally the density of nitrogen at liquid form is

And this is mathematically represented as

=> 
Now the density of gaseous nitrogen is

=> 
Given that the mass is constant


=> 
By using Ohm's law, we can find what should be the resistance of the wire, R:

Then, let's find the cross-sectional area of the wire. Its radius is half the diameter,

So the area is

And by using the resistivity of the Aluminum,

, we can use the relationship between resistance R and resistivity:

to find L, the length of the wire: