Regarding the Red Pyramid height, it was obviously designed to be 200 cubits. It's reported as 105 meters, which would be 344.488 feet. If it was really that height and it was intended to be a perfect 200 cubits then the cubit length of Snefru would be 20.6162857 inches. We know that the cubit length gradually increased over time due to multiple copying errors of the rods so that would be a plausible figure for Snefru's cubit.