1)
Why does the Torah repeat " Asher lo Arba Raglayim"?
1.
Rashi (citing the Sifra): To teach us that if they have five-legs, they are Tahor. 1
2)
What are the implications of "Sheketz Hu"
1.
Sifra: It implies that a mixture is permitted
1
See Torah Temimah, note 70.