According to Figure 13-2, if 25 percent of the parent material remains in a rock sample, how many half-lives have occurred?

Which factor is a density dependent limiting factor on the population of a species? A - predation B-precipitation. C - natural disasters. D - Seasonal variation

What system of your body would be activated if you were surprised? What do the digestive, respiratory, circulatory, excretory systems have in common? What would happen to the human body if one of the organ systems stopped working?

What are the basic requirements for the formation of a thunderstorm? (choose all correct answers.) ?

Select all that are true when a muscle fiber is at rest. a. There is a charge difference across the sarcolemma. b. There is a charge difference across the sarcolemma. c. Sodium-potassium pumps are active. d. Sodium-potassium pumps are active. e.

What does the term adaption mean? How does adaption explain the patterns of distribution of plant and animal species in the world?

What happens to Earth when it is farthest from the sun? It moves fastest. It stops rotating. It moves slowest. It stops revolving.

What are two different habitats in a prairie ecosystem and name one organism found in each habitat.

Which level on the energy pyramid has the third most energy? A. primary producers B. primary consumers C. secondary consumers D. tertiary consumers

How do pH affect the stability of double-stranded nucleic acid?

What is the first step in the scientific process