Two lines are parallel if they have the same slope. Two lines are said to be perpendicular if the product of their slopes is -1.
Note that none of the slopes are equal, so the either are perpendicular or neither.
Note that the product of the slope of line 1 and line 3 is
So, line 1 and line 3 are perpendicular.
For the other cases, it can easily be seen that their are not perpendicular, neither parallel.