{"p":"can-20","op":"mint","tick":"can","amt":"1000","rows":[{"df":"qa","content":[{"q":"What is the impact of blockchain on system security?","a":"Difficult to tamper with data: Each block contains the hash value of the  previous block, forming a chain structure. Once the data in a block changes, it will cause the hash value of the subsequent blocks to change, making it difficult to tamper with the data."}]}],"pr":"93b49390be22dd389031187e9aa9f1125faeec18e2e2c0a8aff373151768ffaf"}