supposed we draw a sample x has n random variables (x1, x2, x3... xn), the sample mean is x̄, and it's variance is s,  the whole population is X, has a mean is μ , variance σ, 

say this specific sample mean x̄ follows a sample distribution W, the variance of this x̄ is V(x̄).

and the variance of this specific sample is V(x),

are V(x) and  V(x̄) exactly the same?

we know that V(x̄) = σ*σ /n

but is V(x)  also equal to σ*σ /n??????