Suppose there is a series of cash flows with an unknown amount x occurring in year 4 , and other known cash flows occurring in different years. Assuming an interest rate of 10% per year, the total future value of all cash flows in year 8 is $20,000. What is the value of x, the unknown cash flow amount occurring in year 4 , that would make the total future value equal to $20,000 in year 8 ? The relevant cash flow series is shown below. Note that you must use linear gradient series factor in your solution. Otherwise (i.e., if you take each value individually to the future), you will not receive points