A retired person wants to invest anamount of 50000. His broker recommends investing in two type of bonds` 'A' and 'B'` yielding 10% and 9%return respectively on the invested amount.He decides to invest at least * 20000 inbond 'A' and at least 10000 in bond 'B' He also wants to invest at least as much inbond 'A' as in bond B'. Solve this line arprogramming problem graphically tomaximise his returns.