The correct plural of appendix depends on the circumstances. If you are talking about the text at the end of a book or article, either the plural appendices or appendixes is correct. If you are talking about the organ in the body, appendixes is the only plural.
The plural form of appendix is appendices.
The singular possessive form is heart's; the plural possessive form is hearts'.
The plural possessive form of "reply" is "replies'".
The plural form is founders. The plural possessive is founders'.
The plural form is valleys. The plural possessive is valleys'.
No, it is singular, the possessive form of it is its. The plural form of it is they or them, and the possessive form is their.To answer the question directly: there is no such word as ITS'.
The plural possessive form of branch is branches'.
The plural possessive form of "mass" is "masses'".
The plural possessive form of "experiments" is "experiments'."
The plural possessive form of "ravine" is "ravines'."
The plural possessive form of "mouth" is "mouths'".