Regarding a Talmudic passage (Brachos 55a) that describes H-Shem figuratively wearing a ring with the word emes (“truth”) imprinted on it, Rashi says one can uncover the true essence of something from its beginning, middle, and end. The letters of emes, are aleph, mem, and suf, the first, middle, and last letters of the Hebrew alphabet, respectively. Rav Yosef Tropper applies this concept to Megillas Esther. The beginning of the sefer shows the Jews in mortal danger, while the end shows the Jews prepared to embark upon the resettlement of the end and the rebuilding of the second Temple. The middle of the sefer contains “my request and my petition.” In other words, the way to bring the Jews from being threatened to thriving is requesting (i.e. praying) to H-Shem.
Perhaps another reason is because the last word of this verse is te’as, (“and it will be done”) and the first word of the next verse is ta’an (“and she answered”), which look somewhat alike and have a difference in gematria of 250 (tzarich iyun). Perhaps there should be a split between what Achashverosh is willing to do and what Esther wants.