Now we see the results of the second coin toss. If heads came up on the first throw, then what are the possible outcomes for the second throw? Either heads or tails could show up on the second coin. In a similar way if tails came up first, then either heads or tails could appear on the second throw.
We represent all of this information by drawing the branches of second coin toss off of both branches from the first toss. Probabilities are again assigned to each edge.