The ability for a country to have access to its resources to creat economic wealth

Three factors create wealth in countries. These factors are the ability to own personal property, a market-driven economy and an infrastructure that provides the basic necessities of life. Private property rights for individuals are key because they provide a reason for individuals to seek economic wealth.Sep 1, 2005

Explanation:

d. new methods of assembly are introduced.

explanation:

this allows for the goods to be made on a larger scale. not faster because now it is shown to be made better, hence the greater productivity in the question. it is calling for something new to be introduced.

the only other powers were germany russia and uk and they were too busy fighting each other wearing each other down   that the us was becoming strong and they were becoming weaker