C is the answer I took a test with the same answer
Ca=40
C=12
O=16
1 mole of CaCO3 has 100 grams
So 50 grams is 0.5 mole
There are nine essential amino acids for humans (histadine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine) that must come from your … food.
Chemical equilibrium<span> is the state in which both reactants and products are present in concentrations which have no further tendency to change with time.
</span><span>Or, we can say that in chemical equilibrium the ratio between the concentration of the reactants and the products is constant.</span><span>
Chemical equilibrium is a result state when </span><span>the forward reaction proceeds at the same rate as the reverse reaction.
</span><span>Different reactions have different equilibrium.</span>