Thanks to Aho and Ullman, Foundations of Computer Science

$1\mathrm{.}1.$ How many nodes are in this diagram?

$1\mathrm{.}2.$ How many links to other nodes $("$edges$")$ are in this diagram?

$1\mathrm{.}3.$ What three nodes is node $"+"$ directly connected to$?$

$1\mathrm{.}4.$ Can you reach node y from node $x?$