4. Assume the total cost of a college education in Singapore will be SGD 250,000 when your child enters college in 18 years. You presently have SGD 43,000 to invest. What annual rate of interest must you eam on your investment to cover the cost of your child's college education? 5. Suppose you are offered an investment that will allow you to double your money in 4 years. You have 20,000 to invest. What is the implied rate of interest? 6. You are looking at two savings accounts. One pays 5.25%, with daily compounding. The other pays 5.3% with semiannual compounding. Which account should you use? 7. If you borrow $100,000 for 30 years in order to buy a house and the interest rate is 7% per year, what will be your monthly house payment? 8. You have determined that you can afford to pay $800 per month toward a new Italian sports car. You call up your bank and find out that the going rate is 12% compounded monthly for 5 years. How much can you borrow? 9. You want to be a millionaire when you retire in 45 years. How much do you have to save each month if you can eam a 12 percent annual return