The periodicity of the properties of elements is chiefly due to the

i) numbers of electrons in the atoms of the elements

ii) distribution of electrons in the atoms of the elements

iii) numbers of neutrons in the atoms of the elements

a) i only

b) i and iii only

c) all of these

d) ii only

e) iii only

f) ii and iii only

g) none of these

h) i and ii only

option A.

Explanation:

african americans demonstrated their newly found freedom by relocating often in search of relatives whom they had been separated from during slavery. others established schools to educate freed people and they built institutions such as churches and political organizations to advocate for their rights.

chemical digestion occurs in the stomach were hcl and pepsin forms chyme, the mouth in which salivary amylase breaks down starch to form bolus, and the small intestine specifically the duodenum.