Learn English – “Innocent” vs. “immature”

Breaking this down:

• and/or is as official as English gets in the sense that you can use it in extremely formal contexts. There is typically a better way to say whatever is being said but it does convey a specific meaning.

• You should use and/or when both options are applicable in its place. "I would like cake and/or pie" means "I would like one or both of the following: cake; pie."

• The main reason for using and/or is to remove the ambiguity of whether and means "only both" and whether or means "only one." And/or explicitly means "it could be one of these or both of these."

• The confusion is drastically exacerbated by mathematicians, logicians and/or computer scientists who are very familiar with the differences between the logical operators AND, OR, and XOR. Namely, or in English can be either OR or XOR; and/or can only mean OR. As you may have noticed, all of the terms look similar which leads to the confusion in parsing sentences like your title.

EDIT: To strictly answer the question, you should use A and B when you explicitly mean both A and B, and you should use A and/or B when you mean A or B (or both).

In response to a request for pronunciation, I typically treat the / as a hyphen and simply say "and or". This is not always standard for the / symbol, however, and other words or phrases with a / may be different.

Sitting at the end of the stairs, sobbing, having lost my love, career and self-respect, I say to myself, "Who AM I? What is the purpose of my life?" See, here it is a question. That's why the helping verb (am) is coming before the subject (I).

I ask myself who I am. Here, it is not a question, a mere narration of what I ask myself. So, it is not ending in question mark, plus, helping verb is after the subject.