How did the last ice age affect human migration? a. it created land bridges where the ocean had once been. b. it required people to create new shelters. c. it required people to form larger communities. d. it required people to live closer together.

Which best describes the scientific method? a. a path of clearly defined steps that must be followed in a particular order b. a possible answer to a scientific question based on knowledge or research c. the recipe for how to conduct an experiment that must be followed precisely d. the process of hypothesis and testing through which scientific inquiry occurs