Answer: 1.23
Explanation: Given that there is no reaction, I will assume that the molarity corresponds to that of a base.
Therefore,
All you have to do is take the negative logarithm of that molarity
Indeed, pOH = -log(5.92x10^-2) = 1.2277 = 1.23
Note:
We could also do this for the pH.
If we were finding the pH, and that we are given the molarity (also known as [OH-]), then, we would also use the negative logarithm (-log (molarity)).
If we wanted to do the opposite, we could find the molarity with the pOH using the inverse logarithm.
10^(-1.2277) = 5.92 x 10^-2