Q. Mr. Jones has $9000 to invest in three types of stocks; low-risk, medium-risk also high-risk. He invests according to three principles. Amount invested in low-risk will be at most $1000 more than amount invested in medium-risk stocks. At least $5000 will be invested in low also medium-risk stock. No more than $7000 will be invested in medium-risk also high-risk stocks. Expected yields are 6% for low-risk, 7% for medium-risk also 8% for high-risk stocks. Elucidate how much money should Mr. Jones invest in each type of stock to maximize his total expected yield?