What is happening to particles of matter while a change of state is taking place

Compare the composition of the moon's surface with the composition of the earth's surface.

The pharynx is the structure in the body that serves as a pathway of both air and food. how does the body make sure that food does not get into the lungs? the salivary glands secrete enzymes that pull food out of the air pathway. the small intestine pushes the air out of the digestive system. the pancreas breaks down food in the air pathway. the epiglottis closes the air pathway so that food will not enter it.

Which two criteria must be met before scientist can use radiocarbon dating? explain your answer