The answer is either Dr Tanenbaum or Dr hong.<span />
http://goblues.org/faculty/grantm/files/2015/12/Practice-Test-3.7-Solutions.pdf
I think it's question number three. Sorry if the link dosen't work.
A=Pe^rt
P=principal(starting)
E= function on calculator
r= rate
T= time (how long)
There isn't a picture to answer the question fully