In a planned​ study, there is a known population with a normal​ distribution, μ=20​, and σ=4. What is the predicted mean if the researcher predicts​ (a) a small positive effect​ size, (b) a medium negative effect​ size, (c) a large positive effect​ size, (d) an effect size of d=0.55​, and​ (e) an effect size of d=−1.40​?
a) μ = 20 + 0.2(4)
b) μ = 20 - 0.5(4)
c) μ = 20 + 1.0(4)
d) μ = 20 + 0.55(4)
e) μ = 20 - 1.40(4)