Apply the same preprocessing steps as in the previous problem.
Let \(\left(v_1, v_2, \ldots, v_n\right)\) be a descending ordering of \(V(G)\) according to vertex degrees, i.e., \(d\left(v_1\right) \geq d\left(v_2\right) \geq \ldots \geq d\left(v_n\right)\). Let \(V_{3 k}=\left\{v_1, \ldots, v_{3 k}\right\}\).
Recall that the minimum vertex degree of \(G\) is at least 3. Show that every feedback vertex set in \(G\) of size at most \(k\) contains at least one vertex of \(V_{3 k}\).