1)
What are the implications of "ve'Zeh D'var ha'Rotze'ach"?
2)
What are the implications of the words "? asher Yakeh es Re'eihu Biv'li Da'as"?
1.
Makos, 7b: It implies that he did not intend to kill at all - but precludes where he intended to kill an animal, a Kuti or a Nefel (an eighth-month baby) and by mistake, killed a Yisrael, who is close to Meizid and does not therefore granted the safety of an Ir Miklat. 1
1
As opposed to someone who deliberately cuts down a tree, which falls on someone and kills him, who is Chayav Galus. See Torah Temimah on Pasuk 5, citing the Sifri, and note 14.
3)
What is the definition of a Sonei?