There are two normally distributed random variables, X N(,²) and Y N(2, 2²). There are two samples, random, i.i.d. sample of the X-values of size n with the sample mean Xbar, and random, i.i.d. sample of the Y-values of size m, with the sample mean of Ybar. Consider anestimator = c₁Xbar + c₂Ybar, where c₁and c₂are two constants.The values of c₁and c₂which make this estimator unbiased are given by c₁= 2-2c₂. Is it true or false?

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