1)
Why is it written v'Lo, and we pronounce it v'Lu?
1.
Radak: The writing means that I would not take 1,000 to do so (and you say that you would have given to me 10)! The pronunciation means that even if you would find someone to give to me 1,000 (I would not do so).
2)
Why did he call him "Ben ha'Melech"?
1.
Malbim: This is a reason not to kill him (even had David not commanded about this).
3)
Whom did David command to guard Avshalom?
1.
Rashi: Whoever will encounter him.
