The half-life of a radioisotope is the amon the symbol 42He, the subscript 2 is the mass number for helium and the superscript 4 is the atomic number for helium.
Fish species B would make a better model organism because at the end they produce 100 eggs more than fish species A.Fish species B is more likely to survive than Fish species A.
eliminates nitrogenous wastes.I think
