When building a pre-stained shelf from Ikea, classify each of the following as useful or not useful for the task: a wooden dowel, a watercolor paint kit, a windowpane, a rubber mallet, a multitool, a screwdriver.

Wooden dowel: useful, a watercolor paint kit: not useful, a windowpane: not useful, a rubber mallet: useful, a multitool: useful, a screwdriver: useful.