Because ∠C ≅ ∠C, the additional bit of information above can be used to show AA similarity.
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None of the other offered choices says anything about <em>both</em> triangles. In order to show similarity, you need information about corresponding parts of the <em>two</em> triangles. Information about one triangle alone is not sufficient.
The total number of outcomes of rolling a die = 6 The total number of outcomes of tossing a coin = 2
The total number of possible outcomes of executing both experiments is 6*2=12, which is also the number of leaves (end of the branch of a tree) on a tree diagram.
