Answer:
The 98% confidence interval estimate of the proportion of adults who use social media is (0.56, 0.6034).
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
.
Of the 2809 people who responded to survey, 1634 stated that they currently use social media.
This means that 
98% 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 98% confidence interval estimate of the proportion of adults who use social media is (0.56, 0.6034).
m<E=45.5 m<F=45.5
this is question 8 can't see question 9
Answer:
B.
Step-by-step explanation:
Green: y = 1.75x + 4
The slope is 1.75 which is the rate per mile.
Green charges $1.75 per mile.
White:
For 3 miles: $10.50
For 5 miles: $13.50
Difference: $13.50 - $10. 50 = $3.00
The $3.00 difference is for 2 miles.
Rate per mile: $3.00/2 = $1.50
White charges $1.50 per mile
Answer: B.
Answer:

Step-by-step explanation:
We can add the two equations to eliminate the variable
and solve for
:



Now, we can use substitution to solve for
:
(given)




Hope this helps :)