No, that's not right.
ihr is one of the trickier words in German, and to understand what it means, you have to look at the case that it's in and whether it's before a noun or not.
(1) Nominative case:
(1.1) standing alone:
- "you (informal plural)": Hans und David, wo seid ihr? "Hans and David, where are you?"
- This one may optionally be capitalised in letters to show respect.
- But not on Duo, because you aren't writing letters here.
(1.2) before a noun:
- A possessive determiner for a masculine or neuter singular noun.
- "her": Julia ist weg aber ihr Teller ist noch da. "Julia is gone but her plate is still here."
- "their": Hans und David sind weg aber ihr Teller ist noch da. "Hans and David are gone but their plate is still here." (i.e. the one plate that belongs to both of them together)
- "your" (something belong to one or more people that you address formally): Herr Müller, Ihr Teller ist noch da.. "Mr Müller, your plate is still there." / Frau Müller und Frau Schulze, Ihr Teller ist noch da. "Ms Müller and Ms Schulze, your plate is still there."
(2) Dative case:
(2.1) standing alone:
- "(to) her": Ich gebe ihr ein Buch "I give her a book"
(2.2) before a noun:
- (this does not happen)
(3) Accusative case
(3.1) standing alone
- (this does not happen)
(3.2) before a noun:
- A possessive determiner for a neuter singular noun.
- "her": Julia hat ihr Buch vergessen. "Julia has forgotten her book."
- "their": Hans und David haben ihr Buch vergessen. "Hans and David have forgotten their book."
- "your" (something belong to one or more people that you address formally): Herr Müller, Sie haben Ihr Buch vergessen. "Mr Müller, you have forgotten your book." // Herr Müller und Frau Schulze, Sie haben Ihr Buch vergessen. "Mr Müller and Ms Schulze, you have forgotten your book."
Capitalised Ihr never means "you" on Duo. Lowercase ihr can mean all sorts of things on Duo, but (nearly?) never "she".
The many meanings of ihr is tied to the many meanings of sie (she; they; (capitalised:) you).
No -- it's just that the possessive determiner corresponding to the polite pronoun Sie (i.e. Ihr, Ihre etc. depending on gender, number, and case of the noun) happens to look like the nominative of the informal second person plural personal pronoun (i.e. ihr) except for capitalisation.
It's not that we use informal "you" as a possessive, any more than in English we would say "you book".
er/ihr sound almost exactly alike with these narrators. Since there's no other context to differentiate in this example, this turn out to be more of a hearing test that a language exercise. Might I suggest using a different subject than you/he in these types of exercises? TYIA.
I don't think any city names have der/die/das in front of them.
Nor do I think that there are countries that have das in front of them.
But countries whose names are grammatically masculine, feminine, or plural require the article: der Irak, die Schweiz, die Niederlande.
(English also has this with plurals -- it has to be "the United States, the Netherlands, the Philippines".)
Sie is used for both singular and plural?
ihr used to be the formal pronoun, but it hasn't been used like that for centuries -- you might come across it in historical dramas or the like, but in modern German, ihr is only informal (and plural).
Sie is the formal pronoun for both one person or multiple people.