StonyLab Borosilicate Glass 1000ml Heavy Wall Conical Separatory Funnel with 24/40 Joints and PTFE Stopcock - 1L (1 Liter)

Dos this come with the stopper or ANY stopper, as pictured?

The stopcock is stuck in place. it won't rotate. i tried adjusting and removing the "nut" at the end but still couldn't rotate it. what did i miss?

Is this foor grade? I want to use it for the hot water reservoir of a coffee dripper system.

Hi, I'm planning on using this with oil. How do you thoroughly clean this after use?