A financial advisor is about to build an investment portfolio client who has 100,000 to invest, The four investments available are A,B,C and D investment. A will earn 4percent and has a risk of "two points" per 1000 invested. B earns 6 percent with 3 risk points, C earns 9 percent with 7 risk points, D earns 11 percent with a risk of 8. The client has put the following conditions on the investments. A is to be more one half of the total invested A cannot be less than 20 percent of the total investment. D cannot be less than C. Total risk points must be at or below 1000. Let A be amount invested in investment A, and define B,C and similarly. Formulate the linear programming model.