Recall that the area under the standard normal curve in-between z₁ and z₂ is:
[tex]P(z_1We know that:[tex]P(z_1Therefore the area under the Standard Normal Curve in-between z = -2.39 and z = 1.03 is:[tex]P(z<1.03)-P(z<-2.39).[/tex]From normal tables we get:
[tex]\begin{gathered} P(z<1.03)=0.84849, \\ P(z<-2.39)=0.0084242. \end{gathered}[/tex]Therefore the area under the Standard Normal Curve in-between z = -2.39 and z = 1.03 is:
[tex]0.84849-0.0084242=0.8400658\approx0.8401.[/tex]Answer: 0.8401.