Assume that firms in a perfectly competitive market are earning economic profits. which of the following statements describes the change in market price and output as a result of the entry of new firms into this market?
a) the short - run market supply curve shifts to the right, causing price to fall and total market output to increase.
b) the short - run market supply curve shifts to the left, causing price to fall and total market output to increase.
c) the market demand curves shifts to the left, causing price to fall and market output to decrease.
d) the market demand curves shifts to the right, causing price to fall and market output to increase.

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?

The wall street journal reported that walmart stores inc. is planning to lay off 2,300 employees at its sam's club warehouse unit. approximately half of the layoffs will be hourly employees (the wall street journal, january 25-26, 2014). suppose the following data represent the percentage of hourly employees laid off for 15 sam's club stores. 55 56 44 43 44 56 60 62 57 45 36 38 50 69 65 (a) compute the mean and median percentage of hourly employees being laid off at these stores. (b) compute the first and third quartiles. (c) compute the range and interquartile range. (d) compute the variance and standard deviation. (e) do the data contain any outliers? (f) based on the sample data, does it appear that walmart is meeting its goal for reducing the number of hourly employees?

Abank has $132,000 in excess reserves and the required reserve ratio is 11 percent. this means the bank could have in checkable deposit liabilities and in (total) reserves.