2572. What characters can be added here so that each character contains a part of the previous character? a) 計 -> _ -> _ -> 堤 b) 粒 -> _ -> _ -> 吹

a) 計 -> 古 -> 吐 -> 堤  

計  KEI, haka(ru), haka(rau) - plan, total, measure

古  KO, furu(i) - old

吐  TOU, ha(ku) - spew, vomit, give vent to

堤  TEI, tsutsumi - bank, embankment, dike

b) 粒 -> 辛 -> 古 -> 吹  

粒  RYUU, tsubu - a grain

辛  SHIN, kara(i) - hot, spicy, trying

古  KO, furu(i) - old

吹  SUI, fu(ku) - blow