You need to add up all the sides of the thing thank you
        
                    
             
        
        
        
Answer:
b) 24
Step-by-step explanation:
We solve building the Venn's diagram of these sets.
We have that n(S) is the number of succesful students in a classroom.
n(F) is the number of freshmen student in that classroom.
We have that:

In which n(s) are those who are succeful but not freshmen and  are those who are succesful and freshmen.
 are those who are succesful and freshmen.
By the same logic, we also have that:

The union is:

In which



So



So the correct answer is:
b) 24
 
        
             
        
        
        
Answer: Here you go
..........................................
 
        
             
        
        
        
Answer:
The sample size is  
Step-by-step explanation:
From the question we are told that 
   The margin of error is E  =  1.5 seconds 
    The standard deviation is  s =  4 seconds 
  Given that the confidence level is 97% then the level of significance is mathematically represented as 
       
=>   
Generally from the normal distribution table the critical value  of   is
 is  
     
Generally the sample size is mathematically represented as 
     ![n  =[  \frac{Z_{\frac{\sigma }{2 } } *  \sigma }{E} ]^2](https://tex.z-dn.net/?f=n%20%20%3D%5B%20%20%5Cfrac%7BZ_%7B%5Cfrac%7B%5Csigma%20%7D%7B2%20%7D%20%7D%20%2A%20%20%5Csigma%20%7D%7BE%7D%20%5D%5E2)
=> ![n  =[  \frac{2.17  * 4 }{1.5} ]^2](https://tex.z-dn.net/?f=n%20%20%3D%5B%20%20%5Cfrac%7B2.17%20%20%2A%204%20%7D%7B1.5%7D%20%5D%5E2)
=>  