1)
How is Hashem "Tov" and "Metiv"?
1.
Radak: You are good, and good comes to me from You, and You do good to all, and You will benefit me, and teach to me Your Chukim.
2.
Malbim: "Metiv" hints to extra benefiting - You will teach to me also Chukim that do not have a reason [that we understand].
