Answer:
The 95% confidence interval estimate for the true proportion of adults residents of this city who have cell phones is (0.81, 0.874).
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
.
For this problem, we have that:

95% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
The lower limit of this interval is:

The upper limit of this interval is:

The 95% confidence interval estimate for the true proportion of adults residents of this city who have cell phones is (0.81, 0.874).
The first square has side lengths of 4 units(because the square root of 16 is 4). The second square has side lengths of 8 units. The third square has side lengths of 12 units. As you can tell, the side lengths increase by 4. So the fourth square will have side lengths of 16 units, and the fifth square will have side lengths of 20 units. The question wants the perimeter, so the answer is 20*4(sum of 4 sides of equal lengths) which is 80 units.