1)
How could Moshe raise his hand on the heaven?
1.
Rashi #1: "Al ha'Shamayim" means (not on the heaven but) towards the heaven.
2.
Rashi (citing the Midrash): Hashem raised Moshe above the heaven.
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Sifsei Chachamim: Thereby epowering him to bring the next three Makos, which took place in the atmosphere. Refer to 9:14:2:1.