Faith Evans Isn't Surprised Tupac Murder Weapon Mysteriously Disappeared

Faith Evans has low, LOW expectations when it comes to cops solving Tupac or Notorious B.I.G.'s murders -- so she's not shocked cops found, then lost, Pac's murder weapon.

We got the R&B singer at LAX, where we broke the news about the Glock that's apparently vanished in a would-be transfer between cops in L.A. and Las Vegas.

Faith was intrigued when we explained how the weapon was unearthed in Compton -- but couldn't hide her disdain for the investigators when we told her about the gun's disappearance.