Why scarcity and choice are basic economic problems faced by every Society??

HELP PLEASE

Using a cps-sample of 7,440 individuals, you estimate the following regression: = 20.91 - 2.61 x female where female is a binary variable that takes on the value of 1 for females and is 0 otherwise. the standard error on the coefficient on female is 0.25. the 95% confidence interval for the gender wage gap, or the amount that females earn less, is: a) [-3.10, -2.12] b) [18.30, 23.52] c) [-3.02, -2.20] d) [-1.96, -1.64]

You are the manager of a large crude-oil refinery. as part of the refining process, a certain heat exchanger (operated at high temperatures and with abrasive material flowing through it) must be replaced every year. the replacement and downtime cost in the first year is $165 comma 000. this cost is expected to increase due to inflation at a rate of 7% per year for six years (i.e. until the eoy 7), at which time this particular heat exchanger will no longer be needed. if the company's cost of capital is 15% per year, how much could you afford to spend for a higher quality heat exchanger so that these annual replacement and downtime costs could be eliminated?

Portionpac has been a good corporate citizen for fifty years. which of the following is not an argument in favor of social responsibility and corporate citizenship?