In traditional two-part epoxy systems, the "A" part consists of an oligomer with terminal epoxy groups, while the "B" part is often a multi-functional amine. Amines react rather quickly with epoxy groups - how might you slow the reaction down to give your customer more time to apply the product? How might you speed it up? Please be as specific as possible (i.e.., saying "use a catalyst" is too generic an answer!).