This one is more substantial than the previous one.
Page 134, next to the last paragraph.
It says that when the black hole is 7 million miles away it's gravity is as strong as the Earth's and thus people float. This makes no sense--the Earth would be falling in, not pegged to the sky.
The only force that people on the Earth would be feeling is the tide and that would only apply in a radial direction. I could believe that it's supposed to be a 1g tide at that distance but I don't think there would be anyone around to experience it--I think the squashing of the planet would have already killed everyone with vulcanism by then.