David used part of $100,000 to purchase a house. of the remaining portion, he invested 1 3 of it at 4 percent simple annual interest and 2 3 of it at 6 percent simple annual interest. if after a year the income from the two investments totaled $320, what was the purchase price of the house?

The management of a supermarket wants to adopt a new promotional policy of giving a free gift to every customer who spends > a certain amount per visit at this supermarket. the expectation of the management is that after this promotional policy is advertised, the expenditures for all customers at this supermarket will be normally distributed with a mean of $95 and a standard deviation of $20. if the management wants to give free gifts to at most 10% of the customers, what should the amount be above which a customer would receive a free gift?

Retirement investment advisors, inc., has just offered you an annual interest rate of 4.4 percent until you retire in 40 years. you believe that interest rates will increase over the next year and you would be offered 5 percent per year one year from today. if you plan to deposit $13,000 into the account either this year or next year, how much more will you have when you retire if you wait one year to make your deposit?

1. which one of the following would be an example of a supply-side market failure? a. a gas station is slowly leaking diesel fuel from its underground tanks, and after the leak is discovered, the business immediately cleans up the pollution at its own expense. b. a gas station is slowly leaking diesel fuel from its underground tanks, but the state uses taxpayer money to clean up the pollution rather than requiring the business to pay. c. your business wants to attract repeat customers by putting on a customer-appreciation picnic at a public park, but you decide not to because you couldn't prevent noncustomers from consuming the food and entertainment you provided. d. everyone rushes to the local retail outlet at midnight on the day of the release of a new video game console, and the store runs out before everyone is able to buy one.