The ancestors of vertex G are , while the descendants of vertex D are/is .The siblings of vertex B areThe number of vertices in the subtree at B equals

To properly address the various components of your question, let's break it down into manageable parts that are typically related to tree or graph structures in computer science.

1. Analyzing Ancestors and Descendants

• Ancestors of Vertex G: The ancestors of a vertex in a tree are all the vertices on the path from that vertex to the root. To identify the ancestors of vertex G, you typically would trace back to the root of the tree, noting each parent until reaching the root.
• Descendants of Vertex D: The descendants of a vertex include all vertices that can be reached by following outgoing edges from that vertex. You would start at D and trace all paths downwards to identify these vertices.

2. Identifying Siblings

• Siblings of Vertex B: Siblings are vertices that share the same parent. To find the siblings of vertex B, identify B's parent and then list all the children of that parent, excluding B.

3. Counting the Subtree Vertices

• Vertices in the Subtree at B: To count the vertices in the subtree rooted at B, perform a traversal of the subtree (for example, using a depth-first search) and count all vertices encountered during this process.

Final Answer

To provide precise answers, specific structures and relationships of the tree or graph would be required. With that said, the exact vertices for the ancestors of G, descendants of D, siblings of B, and the count of vertices in B's subtree cannot be determined without visual representation or additional context about the tree structure.