These questions refer to the above applet.
Points are "collinear" if a line COULD be drawn through the named points (the line does not have to actually be there).
With that in mind, which of the following are collinear? If you aren't sure, use the line tool

to see if a line can be drawn between the two points (click the line tool first THEN click on the two points that you want to draw a line through).