Which expression shows the value of a $2500 investment after it has grown by 4.5% per year for 12 years. a- 2500(1.045)^12
b- 2500(1.045)^144
c- 2500(1.45)^12
d- 2500(1.45)^144

The answer is A. 2500(1.045)^12

This is explained by the formula A(t) = a(1+- r)^t. 
+ for growth
- for decay
t for time

Since this is growth (the word 'grown' in the question gives us an idea), we add 1 to the rate 0.045. 

If you make it a little more clear i can answer it