Use formula to solve this problem (No Excel Please)

Question 10 Five deposits of 400 are made into a fund at 2-year intervals with the first deposit at the beginning of the first year. The fund eams interest at an annual effective rate of 4% during the first four years and at an annual effective rate of 3% after that. There are additional deposits of 500 at 11 and 600 at 12. Find the 2-year interest rate that would prevail during the first 4 years A 0408 B0784 . D. 0816 E The correct answer does not appear