Which statement best describes a solid? D. Its particles are very far apart.
A. Its particles do not move at all.
C. Its particles can flow past each other.
B. Its particles vibrate in place.

What is the primary goal of human communities?

Look at the photo of the leaf. which term best describes this leaf?

1. emigration the movement of people from one place to another 2. immigration a situation in which resources are being used up at a faster rate than they can be replenished 3. migration the leaving of one's homeland to settle in a new place 4. overpopulation the movement of people to a new country 5. sustainable development a situation in which the birth rate is not sufficient to replace the existing population 6. underpopulation the ability to meet current needs without reducing the ability to meet future needs 7. unsustainable development the increase in the population of a city 8. urbanization a situation in which the number of people exceeds the available natural resources in an area