A door-to-door salesperson knocks on Mary's door and convinces her to purchase the Wonder Vacuum for $500. Soon after the salesperson leaves, Mary begins to have second thoughts about the transaction. Which statement about the situation is correct

Sheldon has the following year-end account balances: accounts receivable, $5,000; supplies, $12,000; equipment, $18,000; accounts payable, $17,000; stockholders’ equity, $43,000. the cash account balance was not available at year-end. given the account balances listed, the balance in the cash account should be?

Amachine purchased three years ago for $720,000 has a current book value using straight-line depreciation of $400,000: its operating expenses are $60,000 per year. a replacement machine would cost $480,000, have a useful life of nine years, and would require $26,000 per year in operating expenses. it has an expected salvage value of $130,000 after nine years. the current disposal value of the old machine is $170,000: if it is kept 9 more years, its residual value would be $20,000. calculate the total costs in keeping the old machine and purchase a new machine. should the old machine be replaced?

Ajustification for job training programs is that they improve worker productivity. suppose that you are asked to evaluate whether more job training makes workers more productive. however, rather than having data on individual workers, you have access to data on manufacturing firms in ohio. in particu- lar, for each firm, you have information on hours of job training per worker (training) and number of nondefective items produced per worker hour (output). (i) carefully state the ceteris paribus thought experiment underlying this policy question. (ii) does it seem likely that a firm’s decision to train its workers will be independent of worker characteristics? what are some of those measurable and unmeasurable worker characteristics? (iii) name a factor other than worker characteristics that can affect worker productivity. (iv) if you find a positive correlation between output and training, would you have convincingly established that job training makes workers more productive? explain.