ZR and NG using 16wayOR gate?

Posted by guynextdoor on Jul 08, 2020; 2:01pm
URL: http://nand2tetris-questions-and-answers-forum.52.s1.nabble.com/ZR-and-NG-using-16wayOR-gate-tp4034824.html

I am a bit lost on the ZR and NG part of the ALU

Why can I use 16wayOR gate to compute the ZR function? why do I need 8wayOR function?

I read the sub-bus section and it says:  you must create the narrower bus as an output from a chip-part.

Why do I need to create a narrower bus?

we can have out=out, out=zr, out=ng and work on them using single 16 way OR gate

Thanks for your help