They are doing all sorts of things. they are adding cascades, the machines that have the centrifuges in cascades to enrich more material. so all these things require some answers from them. yeah, of course they do, and it s highly complicated. you say that primarily the sticking points have been political, but there s one sticking point which is very germane to you and your teams in iran. that is, although there s no direct linkage, the iranians are saying they won t agree to thejcpoa being revived unless and until you and your teams stop a different investigation, which is an historic investigation, looking at traces of enriched uranium found in three different sites in iran, which the iranians have kept secret. you re absolutely right. but i have told them, to use your own expression, that unless and until they give us the necessary explanations, we are not going to drop anything we are doing. ....