Should i drop out of school

Which of the following statements accurately describes how costs and benefits are calculated?

Amathematical approximation called the rule of 70 tells us that the number of years that it will take something that is growing to double in size is approximately equal to the number 70 divided by its percentage rate of growth. thus, if mexico's real gdp per person is growing at 7 percent per year, it will take about 10 years(=70/7) to double. apply the rule of 70 to solve the following problem. real gdp per person in mexico in 2005 was about $11,000 per person, while it was about $44,000 per person in the u.s. if real gdp per person in mexico grows at the rate of 5 percent per year: how long will it take mexico's real gdp per person to reach the level that the united states was at in 2005? (hint: how many times would mexico's 2005 real gdp per person have to double to reach the u.s.'s 2005 real gdp per person?

On january 1, 2017, sophie's sunlounge owned 4 tanning beds valued at $20,000. during 2017, sophie's bought 3 new beds at a total cost of $14 comma 000, and at the end of the year the market value of all of sophie's beds was $24 comma 000. what was sophie's net investment