4. You buy a car for $30,000. You make a 20% down payment. What is the monthly payment if the interest rate is 6% and the term is 48 months? 5. You can afford $1,800 per month for a house. You have $50,000 for a down-payment. What is the most you can pay for a house if the interest rate on a 30-year home loan for someone with your credit rating is 4%? 6. You would like to save $500,000 for retirement in 40 years. How much money do you need to invest today to reach your goal if you can earn 6% on your money