__2. se divide en precámbrico, paleozoica, mesozoica y cenozoica. a. cenozoica
b. mesozoica
c. escala del tiempo geológico
d. eones
e. tiempo geológico
g. etapas del desarrollo de la tierra
h. precámbrico
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The characteristic of two different types of reactions are shown below. reaction a: electrons are gained by the atoms of an element. reaction b: protons are lost by the atom of and element. which statement is true about the atoms of the elements that participate in the two reactions? a: their identity changes in both reaction a and b. b: their identity changes in reaction a but not b. c: their identity changes in reaction b but not a. d: their identity remains the same.

Which characteristics can be used to differentiate star systems? check all that apply.

What relationship exists between an enzyme and a catalyst?