unchangeable vs fixed

unchangeable and fixed both are adjectives.

Word	Noun	Adjective	Verb	Adverb
unchangeable	No	Yes	No	No
fixed	No	Yes	No	No

unchangeable (adjective)	fixed (adjective)
not changeable or subject to change	securely placed or fastened or set
	(of a number) having a fixed and unchanging value
	fixed and unmoving
	incapable of being changed or moved or undone; e.g. "frozen prices"