1)
Why does it say "va'Yetz'u"?
1.
Malbim: They did not need to fight, only to chase and make them fall dead.
2)
What is "Beis Kar"?
1.
Rashi citing Targum Yonasan: It is Beis Sharon. Radak - this is like "Kar Nirchav" (Yeshayah 30:23). 1
1
Radak (30:23): This is a pasture full of grain.
