According to the World Bank, the 31 wealthiest countries in the world tended to have much lower rates of and much higher rates of when compared to the 40 poorest countries. A. Infant mortality; adult literacy
B. Internet users; life expectancy
C. Adult literacy; cell phone subscriptions
D. Access to water; access to sanitation

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?