Question: The bamboo-copter was originally conceived by the engineer of what nationality?
Sentence (from "Bamboo-copter"): The bamboo-copter, also known as the bamboo dragonfly or Chinese top (Chinese "zhuqingting" 竹蜻蜓 , Japanese "taketombo" 竹蜻蛉 ), is a toy helicopter rotor that flies up when its shaft is rapidly spun.
Relevant evidence: No