Let's say I am in a library and there is a book on the desk beside mine. If someone who works at the library or someone else studying at the library comes up to me and asks, "Do you know whose this book is" or "Whose is this book," can I answer saying either of these:
One of my friends'.
It's one of my friends'.
I think it would be colloquially okay to say these sentences in the context I provided instead of "It belongs to one of my friends" which is the more wordy version. Do you agree with me? I am asking this because I can hear Americans use the construction, "It is one of my friends' book" but I was just not one hundred percent sure about the construction where the object ("book") is omitted like in "It is one of my friends'."