1)
Check the 1st picture below.
the arrows at the end of the lines are stating that the lines are continuing indefinetely, or namely to infinity, the lines go to infinity upwardly as well as sideways.
3)
Check the 2nd picture below.
the graph has a hole when x = 6 for the domain, meaning it doesn't include that point, but includes any values before it down to -5 and including -5.