Which change would create a new ecosystem? an introduced species

a dam flooding a valley

a lake freezing over

a yearly migration

Average annual precipitation and are the two major features that define the biomes on earth.

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

Isolated volcanic peaks on the ocean floor are