Mrs. Stevens wants to have $18,000 in the bank in 3 years. If she deposits $9,500 today at 4% compounded quarterly for 3 years, how much additional money will she need to add after three years to her investment to make her balance $18,000?

What is the additional amount Mrs. Stevens needs to add to her investment after three years?

a) $8,356.79
b) $0
c) $7,295.16
d) $10,704.84