Which gas did volcanoes not produce in the Precambrian era?
A. Oxygen
B. Carbon dioxde
C. Sulfur
D. Water vapor

Blood has traveled from the heart to the toes. which describes the next step of the circulation process?

(drag each tile to the correct location.) categorize each term as something that is typical of a scientific theory, a scientific hypothesis, or both. - a tentative statement used to guide scientific investigations. - makes predictions about future events. - can be tested by many independent researchers. - based on observations of natural phenomena. - a well-established, highly reliable explanation.

The arrows indicate the direction of wind flow. which place experiences monsoons?