Notre, nos, votre, vos, leur, leurs = our, your, their (possessive adjectives)

Hi Helen,

Normally a collective noun is treated as singular in grammatical terms so you will say -

La police arrive avec ses renforts .

L'équipe a partagé son expérience avec nous.

La famille a dû attendre trois heures avant d'embarquer.

Hope this helps!

Yes. Strictly speaking,

Vous avez passé votre examen means you took  the exam, and

Vous avez eu votre examen is you passed it.

In practice, and according to two native speakers I am in touch with, that distinction is lost in practice.

I am certain from several French teachers that "passer" is used to mean taking a test.  I am told to pass a test in the English sense of pass is "reussir," to succeed.  So the French equivalent of "You passed your test" is "Tu as reussi ton examen."  (I can't type the accents on the e in reussir).