Iis needed to create a chemical reaction

a) oxygen
b) nitrogen
c) carbon dioxide

Up until 1938, paleontologists accepted the idea that coelacanths (an ancient fish) went extinct at the time that they last appear in the fossil record, about 80 million years ago. but in 1938, a live coelacanth was discovered off the coast of south africa that was compared to the fossil record and found to be the same species what goal of science does this discovery represent

Agene editing technology called crispr-cas9 uses cellular machinery to change the cell's genetic material. how might this technology be useful in treating diseases like cancer?

Which nutritional supplement is correctly paired with the health issue it addresses? which nutritional supplement is correctly paired with the health issue it addresses? vitamin c supplementation prevent depression. calcium supplementation increases iq. vitamin e supplementation prevent birth defects. vitamin b12 can vegans maintain health?