Answer:
(22.74,24.06) is the required 95% confidence interval for the population mean ACT score of University of Oklahoma students.
Step-by-step explanation:
We are given the following in the question:
Sample size, n = 121
Sample mean = 23.4
Sample standard deviation = 3.65
Level of significance = 0.05
Degree of freedom 

95% Confidence interval:  
 
  
Calculation of critical value:
 
  
Putting the values, we get,  
 
  
(22.74,24.06) is the required 95% confidence interval for the population mean ACT score of University of Oklahoma students.
 
        
             
        
        
        
Answer:
y = 1
Step-by-step explanation:
 
        
             
        
        
        
The equation of circle is:
(x-a)^2+(y-b)^2=r^2 where C(a, b) is the center.
In order to find r you have to find the distance between C(-2, 1) and let's say A(-4, 1)
The formula for distance is:

r = 2
The equation of circle is
(x+2)^2+(y-1)^2=4
I hope that this is the answer that you were looking for and it has helped you.
 
        
        
        
Using a system of equations, it is found that there are 34 pop songs are on the playlist.
<h3>What is a system of equations?</h3>
A system of equations is when two or more variables are related, and equations are built to find the values of each variable.
In this problem, the variables are:
- Variable x: Number of hip-hop songs.
- Variable y: Number of pop songs.
Brandon has a playlist with 83 hip-hop and pop songs, hence:
x + y = 83.
There are 15 more hip-hop songs than pop songs, hence:
x = 15 + y.
Replacing the second onto the first equation:
x + y = 83.
15 + y + y = 83.
2y = 68.
y = 34.
There are 34 pop songs are on the playlist.
More can be learned about a system of equations at brainly.com/question/24342899
 
        
             
        
        
        
Answer:
a = 8
Step-by-step explanation:
8 + 3 + 1 - 4 = 3a - 2a
8 = a 
a = 8
I hope this helps a little bit.