Trong mô hình hai quốc gia (1, 2) và hai sản phẩm (X, Y): Năng suất X và Y của Quốc gia 1 là x1 và y1; của Quốc gia 2 là x2 và y2. Yêu cầu của qui luật lợi thế so sánh sẽ không thực hiện được khi: a) x1.x2 = y1.y2 (x1 ≠ x2 ≠ y1 ≠ y2).
b) x1.y1 = x2.y2 (x1 ≠ x2 ≠ y1 ≠ y2).
c) x1.y2 = x2.y1 (x1 ≠ x2 ≠ y1 ≠ y2).
d) Cả ba câu trên đều sai.

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?

What two elements normally must exist before a person can be held liable for a crime

Explain whether each of the following events increases, decreases, or has no effect on the unemployment rate and the labor-force participation rate. a. after a long search, jon finds a job. b. tyrion, a full-time college student, graduates and is immediately employed. c. after an unsuccessful job search, arya gives up looking and retires. d. daenerys quits her job to become a stay-at-home mom. e. sansa has a birthday, becomes an adult, but has no interest in working. f. jaime has a birthday, becomes an adult, and starts looking for a job. g. cersei dies while enjoying retirement. h. jorah dies working long hours at the office.