Why are Mercury, Venus, Earth and Mars called the "terrestrial" planets? A. They are all made of rock. B. They have all been able to support some form of life. C. They all have solid cores. D. They all have liquid cores and rocky surfaces.

The image shows ekgs of a person with normal heart waves and of a person having tachycardia. based on this image, what kind of condition is tachycardia? a. the heart beats abnormally fast. b. the heart beats abnormally slow. c. the right atrium of the heart stops working. d. the left ventricle pumps less blood to the aorta.

Control of the body is accomplished by which of the following body systems? nervous system and circulatory system endocrine and repertory system circulatory and respiratory systems nervous system and endocrine systems

Which process of living things produces water that enters the water cycle