文書通信交通滞在費
ぶんしょつうしんこうつうたいざいひ
Diet members' monthly allowance for postage, communication, transport and accommodation
交ぜ書き is read as まぜがき (mazegaki) and means writing some characters (esp. complex kanji) of a compound as kana instead of kanji.
まぜがき
mazegaki
ぶんしょつうしんこうつうたいざいひ
Diet members' monthly allowance for postage, communication, transport and accommodation