What is the main purpose of controlled variables in an experiment?

What is the natural environment? the story of the interaction of people forming societies, cultures, and civilizationsan increase in the world’s temperaturethe process by which social institutions are adopted on a global scalethe natural world in which people, plants, and animals live

Which of the following is one of the innovations that neolithic farmers become more productive? a) plow b) windmill c) tractor d) reaper

Identify the constitutional principle that is common in both this excerpt and federalist no. 51. based on the constitutional principle identified in part (a), explain how the perspective in this excerpt compares with the perspective in federalist no. 51. explain how the constitutional principle identified in part (a) is reflected in the constitution, including two examples to explain how it affects the u.s. political system