Answer:
[tex]Z_{\alpha} = 1.035[/tex]
Step-by-step explanation:
We have that to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval. So:
[tex]\alpha = 1 - 0.85 = 0.15[/tex]
Now, we have to find z in the Ztable as such z has a pvalue of [tex]1-\alpha[/tex].
So it is z with a pvalue of [tex]1-0.15 = 0.85[/tex], so [tex]z = 1.035[/tex]
The answer is:
[tex]Z_{\alpha} = 1.035[/tex]
