1)
Why were Sarei Yizre'el in Shomron?
1.
Radak: Perhaps they went there when they heard about the rebellion, to take counsel; Shomron was the capitol.
2)
What is the meaning of "ha'Omenim Achav"?
1.
Rashi: It is the Omenim (foster parents who raised) of Achav.
2.
Radak: It is the Omenim of Bnei Achav. Gedolim of the city raise the king's sons (verse 6).
3.
Malbim: It is not Samuch. Achav is read with Leimor 1 . I.e. write a letter in the name of Achav saying to command the officers of Yizre'el, the Omenim and Zekenim to fight for his house.