Bari Ender invests 500 at t=0 at a 6% annual rate of simple interest. At t=2 he invests an additional amount so that the balance in his account at t=5 will be 1.000. What annual effective interest rate will Bart's account earn during the 5th year (from t=4 to t=5)? A) 4.84% B) 5.02% C) 5.20% D) 5.44% E) 6.00%