Answer: Option C.
The number of protons and neurons it's contain.
Explanation:
Mass number of an atom is also called atomic mass of an atom which is some what expressed in Dalton i.e 1/2. The mass number is the total number of protons and neutrons altogether called nucleons in an atomic nucleus.
Reactants are the molecules that begin cellular respiration, in this case that would be oxygen<span> and </span>glucose<span>. Hope this helps. </span>
In the given case, Adeline is probably to get scared and shocked regarding menarche as the culture of her time did not assist in educating young women about menarche.
Menarche refers to the initiation of the menstrual cycle, or first menstrual bleeding, in females. From both the medical and social point of view, it is usually regarded as the principal incident of female puberty, as it indicates the probability of fertility.