C.) viruses need a living host to reproduce... this is cause by viruses being Dioxyriboneuclicacid(DNA) surrounded by a protien shell so viruses are not alive per say.... but they get into cells and use living cells to reproduce
The correct answer to this question would be "B", co-dominance.
AB- is the blood type that is least common and 0+ is the most common
The mass number is the sum of the number of protons and number of neutrons the atom has.
So, we can write the equation as:
x + 20 = 40
x = 20 neutrons.