Why is there a Dagesh (dot) in the Reish in ha'Re'isem? Normally, a Reish does not receive a Dagesh!
Radak: This is to strengthen its pronunciation, due to the prefix Hei that indicates astonishment.
Why does it say "Yasrenu"? It should say Yasirenu (Hifil)!
Radak: We find like this - "Rabas Tasrenah" (Tehilim 65:10) is like Tasirenah.
What is the meaning of "Ya'aseh Chafshi"?
Rashi: They will be exempt of rights of the king (Perek 8, to take their property or children).
Targum Yonasan: Ya'aved Chorin Ravrevin. Radak - perhaps this is to exempt them of rights of the king. Or, it is like "Ashrech Eretz she'Malkech Ben Chorin" (Koheles 10:17), "Choreha v'Ein Sham Meluchah Yikra'u" (Yeshayah 34:12) - the most esteemed nobles. I.e. they will be among the highest of the kingdom for everything.