What was the gist of Hashem's answer?
Rashi #2: It was not an answer as much it was a rebuke. Because Moshe queried Hashem's actions, 1 he would see what Hashem was about do to Par'oh, but not what He would later do to the seven nations. 2
Rashi #1 (in Sanhedrin 111a): Having complained about Par'oh's bitter decree, now you will see the miracles that I am about to perform on Par'oh.
Ramban: Hashem assured him that, not only would it not get worse, but that he was about to witness how Hashem would turn the table on Par'oh, with immediate effect, and that his days were about to come to an end.
Seforno: Moshe was now about to witness how, with the same exertion that Par'oh applied to hold on to Yisrael and to scatter them throughout the land, Par'oh would exert himself - not only to expel them, but to make sure that every last one of them leaves. 3
Rashi: Not like Avraham, who, after being told that Yitzchak would be his seed, said not a word when Hashem ordered him to bring him up as an Olah.
This was the first reason why he did not merit to take Yisrael into Eretz Yisrael. However, he could still have overturned the decree through Tefilah, which was no longer possible after he struck the rock, where Hashem decreed with an oath that he would not enter Eretz Cana'an. Refer also to 6:3:1:2 and notes.
Midah ke'Neged Midah.
What are the connotations of "Ki be'Yad Chazakah Yeshalchem"?
Rashi, Targum Onkelos and Targum Yonasan: He will send them out on account of Hashem's strong Hand (that will eventually force him to capitulate).
Rashbam: Pharaoh will expel Yisrael with a strong hand, to force them to leave against their will. 1
Seforno: Pharaoh will go to the n'th degree to expel Yisrael.
With whose strong hand will Pharaoh expel Yisrael from his land?
Rashi and Rashbam: He will expel Yisrael due to the strong hand Hashem, and force Yisrael to leave against their will 1 with his (Pharaoh's) strong hand.
Targum Onkelos and Targum Yonasan: He will expel them too, on account of Hashem's strong Hand.
Why are there multiple expressions "Yeshalchem... Yegarshem", Garesh Yegaresh (11:1)?
Rashi: Refer to 6:1:3:1.
Rosh: Midas ha'Din argued that 400 years of servitude were decreed. In order to reduce them, it was necessary that Pharaoh explicitly free them (the repetitions teach this).
Seforno: Refer to 6:1:1:4.
QUESTIONS ON RASHI
Rashi writes that Avraham did not question Hashem. Avraham said "ba'Mah Eda"!
Da'as Zekenim, Hadar Zekenim, Riva: Avraham did not question Hashem, he merely asked to know the merit in which he will inherit the land. Hashem answered, in the merit of Korbanos.
Rashi writes that because Moshe questioned Hashem, he would not see what He will do to the seven nations. Below, "Ya'an Lo He'emantem Bi", connotes that it was due to Mei Merivah!
Riva: Questioning Hashem caused that Moshe not see vengeance against the seven nations. Due to Mei Merivah, he could not enter Eretz Yisrael.
Refer to 6:1:1:1**.