1- We know that mining requires lots of electricity. A solution can be choosing a node randomly, and that node puts the transactions inside a block and adds the block at the end of the chain. Then we repeat this process again and again, so we do not need any miner. What are the threats of such a solution? Explain in details with some examples. 1- We know that mining requires lots of electricity. A solution can be choosing a node randomly, and that node puts the transactions inside a block and adds the block at the end of the chain. Then we repeat this process again and again, so we do not need any miner. What are the threats of such a solution? Explain in details with some examples