A) 5
Half-life is the time it will take for a quantity to reduce to half its initial value. In this case, uranium will undergo radioactive decay, and after 700 mil years, 5 of the 10 uranium atoms will have decayed.
The nucleus contains the <u>DNA</u> (Deoxyribosenucleic Acid). It codes for all the hereditary characteristics an organism has and it is packaged into chromosomes within the nucleus.