Find the value of the unknown quantity X in the following diagram, such that the equivalent cash outflow equals the equivalent cash inflows when, 1. Interest rate = 15 % per year. 2. Interest rate = 15% per year compounded quarterly. 15% per year compounded continuously 3. Interest rate A1=$1200 A2=$600 0 10 7 8 9 4 6 1 2 $1200 X X4