Answer:I think the answer is letter B.
Step-by-step explanation:
You put the x=6
6³-4(6)²-12(6)+15=15
Answer:
D.2.58
Step-by-step explanation:
We have that to find our
level, that is the subtraction of 1 by the confidence interval divided by 2. So:

Now, we have to find z in the Ztable as such z has a pvalue of
.
That is z with a pvalue of
, so Z = 2.58.
The answer is given by option D.