Suppose A, B, C and D all make their first carrier sense, as part of an attempt to transmit, at the same time. Draw a timeline showing one possible sequence of transmissions, attempts, collisions, and exponential backoff choices. Your timeline should also meet the following criteria: (i) transmission attempts should be all stations at the same time but successful transmissions should be in the order A, CB D and (ii) there should be at least three collisions. Specifically mention the backoff choices of each station.