4. Even when all nodes are honest, blocks will occasionally get orphaned: if two miners Minnie and Mynie discover blocks nearly simultaneously, neither will have time to hear about the others block before broadcasting hers. 4a. What determines whose block will end up on the consensus branch? 4b. What factors affect the rate of orphan blocks? Can you derive a formula for the rate based on these parameters? 4c. Try to empirically measure this rate on the Bitcoin network. 4d. If Mynie hears about Minnies block just before shes about to discover hers, does that mean she wasted her effort? 4e. Do all miners have their blocks orphaned at the same rate, or are some miners affected disproportionately?