10. A security generates a fixed yet unknown cash flow of some amount for each of the first three years (i.e. t=1,t-2, and t-3), and then $1,000 per year for each of the remaining seven years (t=4 through t=10). The present value of the cash flows at an interest rate of 8% is $10,504.80. What annual cash flow does the security pay for years 1, 2, and 3