Explanation:
From the question it can be infered that initially only parent atoms were present in the rock and no daughter atom. So, initially there was only uranium atom and no lead atom. So, in total there were 500+1500= 2000 uranium atom. And no lead tom was there.
Answer:
Try to think those who are made from amino acid... melatonina it is a tryptophan precursor, norepinephrine comes from tyrosine, epinephrine also comes from tyrosine and phenylalanine, the thyroid hormone comes from tyrosine too, but the TSH is derivated from TRH. Last option is not an amino acid derivative.
Explanation:
Answer
there are to answers one is an answer to a problem or a mixture of chemicals
Explanation:
One month after the full moon is another full moon.
Hope this helps :)