Suppose we measure the noise in a resistor (with no applied voltage) and find that the noise voltage exceeds 10 µV 5% of the time. We have reason to believe the noise is well modeled as a Gaussian random variable, and furthermore, we expect the noise to be positive and negative equally often so we take the parameter, m , in the Gaussian PDF to be m = 0. Find the value of the parameter, σ2. What units should be associated with σ2 in this case.