Let X, Y each be random variables with means X = Y = 3 and standard deviations X = 4 and Y = 2. (a)

Let X, Y each be random variables with means μX = μY = 3 and standard deviations σX = 4 and σY = 2.

(a) Compute σ2X−Y if X and Y are independent.

(b) Compute σ2X−Y if X and Y have correlation ρ = 0.5.

Please show and demonstrate how to do each step of the question - I have no idea where to begin! Thanks.