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Given that Var(X) = 5 and Var(Y) = 3, and Z is defined as Z =...

Given that Var(X) = 5 and Var(Y) = 3, and Z is defined as Z = -2X + 4Y - 3.

(a) Find the variance of Z if X and Y are independent.

(b) If Cov (X,Y) = 1, find the variance of Z.

(c) If Cov (X,Y) = 1, compute the correlation of X and Y.

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