Answer:

Step-by-step explanation:
We are given zeros as x=-4, x=-2
so, we can set up function as

Vertex is at (-1,3)
It means that graph passes through point (-1,3)
so, we can plug x=-1 and f(x)=3
and then we can solve for 'a'

we get 

now, we can plug it back 
and we get 

now, we can simplify it 

 
        
             
        
        
        
(-2,-3) 
I. (+,+)
II. (-,+)
III. (-,-)
IIII. (+,-)
        
             
        
        
        
Step-by-step explanation:




Swap x and y

 
        
             
        
        
        
Answer:
I think it is the second one because -4 is the least
Step-by-step explanation:
 
        
                    
             
        
        
        
Answer:
(0.4958, 0.7422)
Step-by-step explanation:
Let p be the true proportion of water specimens that contain detectable levels of lead. The point estimate for p is  . The estimated standard deviation is given by
. The estimated standard deviation is given by  . Because we have a large sample, the 90% confidence interval for p is given by
. Because we have a large sample, the 90% confidence interval for p is given by  where
 where  is the value that satisfies that above this and under the standard normal density there is an area of 0.05. So, the confidence interval is
 is the value that satisfies that above this and under the standard normal density there is an area of 0.05. So, the confidence interval is  , i.e., (0.4958, 0.7422).
, i.e., (0.4958, 0.7422).