Correct Answer - Option 2 :

\(\sigma \)
__Explanation:__

The population mean and standard deviation are two common parameters. In statistics, Greek symbols usually represent population parameters, such as μ (meu) for the mean and σ (sigma) for the standard deviation.

\(̅{X}\) = The sample mean formula is:

\(̅{X}\) = ( Σ xi ) / n

Population standard deviation = Standard deviation measures the spread of a data distribution. It measures the typical distance between each data point and the mean.

**σ** =√([Σ(x - u)2]/N)]

**S = Sample standard deviation =** σ =√([Σ(x - x̅ )2]/(n - 1)]