{"p":"can-20","op":"mint","tick":"can","amt":"1000","rows":[{"df":"qa","content":[{"q":"What are the challenges in protecting privacy in blockchain?","a":"Limited scalability: The privacy protection mechanisms in blockchain technology are generally not scalable, which means that as the number of"}]}],"pr":"92a6a8674c7d9bd532381a7b5969e1b65be3f3fc07dd40bf9c0ad99d29eecfeb"}