Yes it is, common nouns are basically the more specific version of nouns
hope this helps!!
Oh, I was thinking of something very different but anyway i think its D
It is a bit confusing on why you said 40,0000 with four zeros
But based my assumptions with calculations, here are my answers:
40,0000 with five zeros or 400,000÷60=6666.67
40,000 with four zeros=666.67