1)
Whom did he take from the royal seed?
1.
Rashi: Tzidkiyah. Malbim - "v'Lakach mi'Zera ha'Aretz" (5) hints to this.
2)
What is the significance of the Bris?
1.
Radak: This [and the curse] were Tzidkiyah will not rebel, and he will be submissive to Nebuchadnetzar and not be haughty against him. Also, he took the officers to be guarantors for this.
2.
Malbim: "Va'Yitenehu bi'Sdei Zara" (5) hints to this.
3)
Who are "Eili ha'Aretz"?
1.
Rashi: The officers of the land. Malbim - "Tzaftzefah Samo" (5) hints to this.