You would observe, trying to identify if there's a minimum difference in each beaker. Like, colour, or using an <em>bagueta </em>(idk how to say it in english), churning it or something like that.
Answer:
no hablo espanol ok? sorry
Answer : The molar concentration of ethanol in the undiluted cognac is 8.44 M
Explanation :
Using neutralization law,

where,
= molar concentration of undiluted cognac = ?
= molar concentration of diluted cognac = 0.0844 M
= volume of undiluted cognac = 5.00 mL = 0.005 L
= volume of diluted cognac = 0.500 L
Now put all the given values in the above law, we get molar concentration of ethanol in the undiluted cognac.


Therefore, the molar concentration of ethanol in the undiluted cognac is 8.44 M