How is relative-age dating used to determine the ages of fossils? -by observing the formation of sedimentary rocks -by using radioactive isotopes -by estimating the number of fossils in a particular region -by the formation of igneous rocks -by identifying the way the fossils were formed

Nerve cells are specialized to respond to stimulitrue or false?

Diagram of the evolution of land plants?

The image below shows a common blood pressure gauge. what does this device do? a. measures the level of oxygen present in the blood b. measures the pressure of blood when the lungs expand and compress c. measures the electrical activity of the heart d. measures the pressure of blood when the heart contracts and relaxes