Answer:
a) 化 -> 旨 -> 冒 -> 眺
化 KA, KE, ba(keru) - transform
旨 SHI, mune - purport, content, instruction
冒 BOU , oka(su) - risk, brave, deft, dare, desecrate
眺 CHOU, naga(meru) - look at, watch, gaze
b) 墜 -> 埋 -> 野 -> 預
墜 TSUI - fall to pieces, collapse, demolish
埋 MAI, u(maru), u(meru), u(moreru) - bury, be buried, filled up
野 YA, no - field, plain
預 YO, azu(keru), azu(karu) - entrust