Answer:
              
Step-by-step explanation:
              
 
        
             
        
        
        
Answer:

13 glue sticks cost $25.22.
Step-by-step explanation:
4 blue sticks cost $7.76, this means that one glue stick costs 
$7.76/4 = $1.94.
Let 
 be the cost of the glue sticks, and 
 be the number of glue sticks; then

We can use this equation to find the cost of 13 glue sticks; we just put 
 into our equation and it gives:

So 13 glue sticks cost $25.22.
 
        
                    
             
        
        
        
Answer:
This is an exponential growth problem.
  
The growth rate is 4% (0.04).
The time is 10 years (10 years from 2005 to 2015)
  
A = P(1+i)t
A = amount spent in 2015
P = amount spent in 2005
i = interest rate expressed as a decimal
t = # years
  
A = 500(1.04)10
A = 500(1.480244)
A = 740.122 ==> 740 billion
Step-by-step explanation:
 
        
             
        
        
        
Answer:
C.
Step-by-step explanation: