(a) According to the Tana Kama, a piece of Kodshei Kodshim, and one of Pigul or Nosar (or Tamei [see Tos. Yom-Tov]) fell into pieces of Chulin or of Kodshim Kalim (see Tiferes Yisrael), assuming that the latter contained sufficient to render one of them Batel (but not both) - they are Asur to Zarim, but Kohanim may eat them (The Rambam explains the Mishnah quite differently [see Tos. Yom-Tov]).
(b) R. Shimon - permits them to Zarim as well.
(a) If a piece of Kodshei Kodshim and a piece of Kodshim Kalim are cooked together with a piece of Basar Ta'avah (see Tos. Yom-Tov), which contains sufficient to render either of the Kodshim pieces Batel - the mixture is permitted Tehorim (even Zarim) even according to the Rabbanan, and forbidden to Teme'im (even Kohanim) ...
(b) ... even according to R. Shimon.