2099. What characters can be added here so that each character contains a part of the previous character? a) 警 -> _ -> _ -> 餓 b) 妄 -> _ -> _ -> 幸

a) 警 -> 詳 -> 養 -> 餓  

警  KEI - admonish, warn

詳  SHOU, kuwa(shii) - detailed, full, familiar with

養  YOU, yashina(u) - rear, support, adopt

餓  GA - starve

b) 妄 -> 如 -> 吐 -> 幸  

妄  MOU, BOU - without reason, without authority

如  JO, NYO - equal, like, as, as if

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

幸  KOU, shiawa(se), sachi - happiness, good fortune