1)
Is this the same Charim as in verse 32?
1.
Rashi (36): (No.) Before verse 36 counts Bnei Yehudah and Binyamin; from there, the verses count Kohanim and Leviyim - "va'Yakumu Roshei ha'Avos li'Yhudah u'Vinyamin veha'Kohanim veha'Leviyim" (1:5). Malbim (36) - and after, it counts the Nesinim, who served the Kohanim.
2.
Ibn Ezra: Yes 1 .
3.
Metzudas David: No. Above, there were only 320 Bnei Charim.


