Approximately how much did united states owe to other countries at the end of the revolutionary war

What impact did improvements in farming technology near the end of the nineteenth century have on the american economy? a. more energy was needed to power equipment, creating the renewable energy industry. b. less labor was necessary on farms, leading workers to pursue other jobs. c. less money was invested in farming as many locally owned farms went bankrupt. d. more demand for agricultural products reduced the price of food and animal products.

Whether or not a given study has the possibility of causing harm to participants:

Which example define natural rights ?