An isotope of yttrium has 39 protons and 59 neutrons. What is the mass number of that isotope?

answer

fusion: the energy source of stars. the energy released from the collapse of the gas into a protostar causes the center of the protostar to become extremely hot. when the core is hot enough, nuclear fusion commences. fusion is the process where two hydrogen atoms combine to form a helium atom, releasing energy.

hope it

the atomic mass is the bottom number on the element.

-steel jelly

58750.08068 is the answer i think