Transaction propagation time

let say i use my kernel to do A SEND, is there is way to measure how long does it take to have it propagate to all nodes world-wide

same for block propagation time. that is if some node solve the puzzle, announce it. how long does it take for the anouncement to get to all nodes

and if i understood correctly every nodes in the AION network suppose to verify and validate it …

how the consensus actually implement. for example if i mine a block, make announcement to my peers I guess my peers validate it and relay to its peers and the same process repeat until all NODES receive it … so only when the last node receive, verify and validate it then only then it’s final ? if any one node does not agree with it then my mined block is not valid ???