Which example from the text develops the idea that it remains a mystery as to how the Egyptians moved and stacked the stones they used to build the pyramids? "Perhaps they used systems of ramps, ropes, and plain, old-fashioned elbow grease..."

"The Great Pyramid weighed approximately 5,750,000 tons. A draft horse can pull four tons on its own..."

"But the ancient Egyptians didn't use horses, and they certainly didn't have pickup trucks."

"A team from the French Institute for Oriental Archaeology discovered a unique ramp system..."