Evan deposits $500 in a savings account that earns interest. Let f(t)=500 and g(t)=1.05t, where t represents the time, in years, since the account was opened.
Which expression models the amount of interest, in dollars, earned on the account as a function of time?
A. f(t)⋅g(t)

B. g(t)−f(t)

C. f(t)+f(t)⋅g(t)

D. f(t)⋅g(t)−f(t)