What would a loss of resources do to a country’s production level?

Why are low-lying lands more suitable for agriculture than hilly areas?

How important is it to have a powerful army and navy? give two reasons for your answer

Chen's research team randomly assigned some newborns and their mothers either to a breastfeeding promotion group (where breastfeeding was encouraged, but not required) or to a normal pediatric care group (where breastfeeding was neither encouraged nor discouraged). which research method did they use?