ok, well here is the exact details of the problem:
which fatty acid melts at the highest temperature (solid to liquid)
(order from lowest to highest temp required to melt)
Don't know how to draw on here, so i will just explain it to you
1) a 17 long hydrocarbon chain with a Carboxyl group attached at the end. Has no double bond
2) a 17 long hydrocarbon chain with a Carboxyl group attached at the end. Has 1 double bond
3) a 17 long hydrocarbon chain with a Carboxyl group attached at the end. Has 2 double bonds.
My guess is that 1 requires least and 3 requires most temperature