New brothread - Single Huge Spool 5000M Each Polyester Embroidery Machine Thread 40WT for Commercial and Domestic Machines - Yellow

Probably a stupid question but why does the dark gray - 707 look nothing like a dark gray but more of a dark blue?

What ply is this thread?

Can this be used in a regular Brother sewing machine for quilters, not an embroidery machine, and does it do well? (with a stand for threading)

What does the N in front of the number mean?