Species can vary in several ways. which of the following is one of dawin's ideas that was acceped by most scientists of his time due to the large number of fossils being discovered at that time?

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