Consider the following directed graph for the following questions:

If E is the initial state and B is the goal state, the first few vertices expanded by a Depth$-$first TREE search with loop checking are $($enter the single letter label of a node$)$: Need help filling in the last $5.$ Thanks!

$1.$E

$2.$H

$3.$

$4.$

$5.$

$6.$

$7.$