1)
Above (verse 6), he said "Eich Atem No'atzim." Why did he say now "Mah Atem No'atzim"?
1.
Malbim: He already heard from the Zekenim that he cannot turn the people away empty without fulfilling their request at all. He now asked how much to fulfill it.
2)
Why did he say "Nashiv"?
1.
Malbim: The officers of counsel are partners in conducting the kingship. This matter is relevant also to them.