3) The others points would be (1, -1) and (-2, 2).
This answer can be derived by the fact that you add 3 units to either the x or y value of the known points based on whether you are moving up the y axis or across the x axis.
4) 18mi south = 18 units down the y axis so (-16, 15) becomes (-16, -3)
5) The distance traveled is just the difference between the y values. 9 --> -7 is 16 units, so they traveled 16 blocks