1)
Why is there an extra ?Mem? in ?ha?Pidyom??
1.
Rashbam: The Torah sometimes adds ?Mem? ? as in ?Reikam? Bereishis, 41:32?, and ha?Kinam? Sh?mos, 8:13.
2)
To whom is "Peduyei ha'Levi'im" referring?
1.
Rashi: It refers to the twenty-two thousand firstborn who were redeemed by the bodies of the twenty-two thousand Levi'im.