No way to tell if it's a slam-dunk from the photos IMHO.
Read the ad

Seller replaced some things that needed to be replaced and sells it as "Ready to ride"... of course it could still be a trainwreck but for a newbie who knows nothing about bikes but wants to spend $100 on a used bike, this one is worth investigating imo. definitely looks to be a better deal that the one the OP posted. in my city it would be sold already