I have a few questions about code sections. #1) If you have a light fixture on s grid ceiling and it is cord connected, is the receptacle allowed to be above the ceiling tile? Is code sec. 400-8 (2) the only section that applies here? Any other setion.

#2) You have a BX wire running into a metal light fixture box. This light is effectivly grounded right? Section 250-136(a)

#3)We all know that you shouldn't leave wires hanging out without boxing them off. (Does it matter if they are dead?)Would section 300-15 cover this issue?
Am I missing another code section for any of the above questions?