What are some of the causes of background and mass extinctions

How does an angiosperm prevent self pollination

About __ of the mass of the cell is water

Iwill mark which of these statements best describes how nasa's kennedy space center benefits florida? it improve the average income of people. it encourages the use of science for entertainment. it produce more astronauts and space scientists in florida. it encourages people in florida to use space technology in homes.