It is very probable that his first victim was in London.
The best person to answer that would be Jack himself. Or maybe he was bonkers.
If you mean Jack The Ripper it is impossible to tell due to the fact that there are differing opinions on who his first victim was.
Annie Chapman
Fridays
It is presumed 'Jack' used a knife.
Jack killed 30 September 1888.
midnight
As far as we know - yes.Yes he did
30 Sept. 1888
Catherine Eddowes.
A guys called Jack The Ripper
If you mean Jack the Ripper, he killed his victims with a knife, cutting the throats of women and then cutting out vital organs.