Answer:
a. .92
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence level of
, we have the following confidence interval of proportions.

In which
z is the zscore that has a pvalue of
.
The margin of error of the interval is:

The lower bound is the point estimate
subtracted by the margin of error.
The upper bound is the point estimate
added to the margin of error.
Point estimate:
The confidence interval is symmetric, so it is the mean between the two bounds.
In this problem:

Sample of 400, which means that 
Margin of error is the estimate subtracted by the lower bound. So 
We have to find z.




has a pvalue of 0.96.
This means that:




Confidence level:

So the correct answer is:
a. .92
Answer:
I have no idea sorry for wasting your time
Step-by-step explanation:
1.86 : 2 = 186 hundredths : 2
1.86 : 2 = 93 hundredths
1.86 : 2 = 0.93
From the function y=x^2-4x+7
to complete the square we proceed as follows:
The vertex form is given by:
y=(x-h)^2+k
where (h,k) is the vertex:
thus from the function we shall have:
y=x^2-4x+7
c=(b/2a)²
c=(4/2)²=4
thus adding an subtracting 4 in the expression:
y=x^2-4x+4-4+7
y=(x-2)^2+3
thus the vertex will be:
(2,3)
The answer is:
<span>D. Minimum at (2, 3)</span>