To solve for the A or the principal amount plus interest you can use two formulas:
A = P + I
Where: P = Principal
             I  = Interest
or you can use 
A = P (1+ rt)
Where: P = principal
             r  = rate in decimal
             t  = time in years
With your given you can use the second one, without having to use the first. 
Given that the Principal amount is $222 and the rate is 12% and time is 10 years, we first need to convert your rate into decimal by dividing the value in percent by 100 which will yield 0.12. 
Then now we can just input the data that you know into the formula:
A = P(1+ rt)
   = $222(1 + (0.12)(10))
   = $222(2.2) 
   = $488.40
Your A is then equal to $488.40
If you need to get the simple interest all you need to use is the first formula given:
A = P + I
for the interest you transpose the P to the side of the A and you will get:
I = A - P
  = $488.40 - $222
  = $266.40
$266.40 is the added interest to the principal amount. 
        
             
        
        
        
Answer:
I think its C
Step-by-step explanation:
Sorry if im wrong
 
        
             
        
        
        
Total are of Rhode Island = 1500
        
             
        
        
        
Answer:
(a) 8.15
(b) 12.92
Step-by-step explanation:
Given: P = $3000, r = 0.085
                 
Where 
A is the Amount
P is the Principal
r is the rate 
t is the time
(a) For the amount to double, A = 2 × P
                A = 2 × $3000
                A = $6000
                
                
                
Take  of both sides
 of both sides
                
But 
             ∴ 
                
                
                t = 8.15
(b) For the amount to double, A = 3 × P
                A = 3 × $3000
                A = $9000
                
                
                
Take  of both sides
 of both sides
                
But 
             ∴ 
                
                
                t = 12.92
 
        
             
        
        
        
i think its d! hope that helps! is that flvs?