Debts of $$7000$ due in one and a half year, and $$11000$ due in three years are to be settled by a single payment one year from now. What is the size of that single payment if interest is $7\mathrm{.}5\%$ compounded monthly? FV$1=?$ FV$2=?$ I$/$Y$=?$ C$/$Y$=?$ n$1=?$ n$2=?$ PV$1=?$ PV$2=?$ Single payment E after one year $=$ $ $\_\_\_\_\_\_\_\_\_\_\_$ up to $2$ decimal places