1)
Seeing as Hashem replaced the Bechoros with the Levi'im, why do the Bechoros still require Pidyon?
1.
Seforno: Because that replacement was confined to that generation only.
2)
Having already written "Velakachti osam Li" - in Pasuk 16, why does the Torah repeat it here?
1.
Ibn Ezra and Moshav Zekenim: This Pasuk is connected with the coming Pasuk (as is common). When I took the Levi'im, I gave them to Aharon and his sons.
