Answer:
4. It should be less than coefficient on str in the first regression
Step-by-step explanation:
Since the str and income are positively correlated and the coefficient on income in the second regression is positive, the coefficient on str in the second regression therefore should be less than coefficient on str in the first regression.
 
        
             
        
        
        
Answer:
419.25
Step-by-step explanation:
The calculation of the cost of materials for the cheapest such container is shown below:-
We assume
Width = x
Length = 2x
Height = h
where, length = 
Base area = lb
= 
Side area = 2lh + 2bh
= 2(2x)h + 2(x)h
= 4xh + 2xh
Volume = 24 which is lbh = 24

Now, cost is 

now we have to minimize C(x)
So, we need to compute the C'(x)

C"(x)  
now for the critical points, we will solve the equation C'(x) = 0


So, x is a point of minima that is
= 
Now, Base material cost is
 
= 139.75
Side material cost is
 
= 279.50
and finally 
Total cost is 
= 139.75 + 279.50
= 419.25
 
        
             
        
        
        
Its Letter A see photo for solution
 
        
        
        
Divide the nonagon radially into 9 congruent, equilateral isosceles triangle. Each triangle has vertex angle of 360°/9 = 40°.
Interior angle of polygon = 180°-40° = 140°. 
Sum of interior angles = 9(140°) = 1260°