He wasn’t a zombie. He was lich, maybe a wight. Also, he quit carpentry years before he died.

As someone who does speak native English, no clue. My best guess is that it is a typo. I think it was supposed to be $40m.

Most of the “chasm of ignorance” is the stuff we know that we don’t know. We don’t know what dark matter is made of. We don’t know what dark energy is. We don’t know how to reconcile quantum mechanics and general relativity.