Net exports might be a negative amount if americans
- decrease their holdings of foreign currencies, borrow from foreigners, or do a little of both.
- increase their holdings of foreign currencies, borrow from foreigners, or do a little of both.
- decrease their holdings of foreign currencies, lend to foreigners, or do a little of both.
- increase their holdings of foreign currencies, lend to foreigners, or do a little of both.

American gas products manufactures a device called a can-emitor that empties the contents of old aerosol cans in 2 to 3 seconds. this eliminates having to dispose of the cans as hazardous wastes. if a certain paint company can save $75,000 per year in waste disposal costs, how much could the company afford to spend now on the can-emitor if it wants to recover its investment in 3 years at an interest rate of 20% per year?

You and your new australian bride matilda, are applying for a loan and are required to submit a balance sheet with your net worth. you own a 2008 toyota camry that you bought last month for $9,995. the kelly blue book value for this car is $13,995. you owe $8,150 on the car loan for the camry. you pay off your visa credit card every month and have not paid any credit card interest this year. the current visa credit card balance is $3,522, and the next statement is due in 15 days. you have a student loan balance of $6,500. you presently have $425 in your checking account and $1,540 in your savings account. you own 100 shares of ibm stock that you purchased for $85.50 per share. one share of ibm is now selling for $158.42. you own computers and other electronics that you purchased for $4,100 but could probably sell today on e-bay for $1,800. your gross income is $80,000 per year. what is your current net worth? (see wb ch. 2 example 2.3)

5. profit maximization and shutting down in the short run suppose that the market for polos is a competitive market. the following graph shows the daily cost curves of a firm operating in this market. 0 2 4 6 8 10 12 14 16 18 20 50 45 40 35 30 25 20 15 10 5 0 price (dollars per polo) quantity (thousands of polos) mc atc avc for each price in the following table, calculate the firm's optimal quantity of units to produce, and determine the profit or loss if it produces at that quantity, using the data from the previous graph to identify its total variable cost. assume that if the firm is indifferent between producing and shutting down, it will produce. (hint: you can select the purple points [diamond symbols] on the previous graph to see precise information on average variable cost.) price quantity total revenue fixed cost variable cost profit (dollars per polo) (polos) (dollars) (dollars) (dollars) (dollars) 12.50 135,000 27.50 135,000 45.00 135,000 if the firm shuts down, it must incur its fixed costs (fc) in the short run. in this case, the firm's fixed cost is $135,000 per day. in other words, if it shuts down, the firm would suffer losses of $135,000 per day until its fixed costs end (such as the expiration of a building lease). this firm's shutdown price—that is, the price below which it is optimal for the firm to shut down—is per polo.