david wants to invest atmost Rs.12000 in bonds A and B .Acoording to the rule ,he has to invest atleast Rs. 2000 in bond A andatleast Rs. 4000 in bond B. If the rates of the interest on Bonds A and B are 80% and 10% per annum ,formulate the problem as L.P.P and solve graphically for maximum interest. Also determine the maximum interst received in a year.