Let X1,..., Xn and Y1,..., Yn be independent samples from N(, 2) and N(, 2), respectively.

Let X1,..., Xn and Y1,..., Yn be independent samples from N(ξ, σ2) and N(η, τ 2), respectively. Determine the sample size necessary to obtain power ≥ β against the alternatives τ/σ > when α = .05, β = .9, = 1.5, 2, 3, and the hypothesis being tested is H : τ/σ ≤ 1.