For this problem, you had to draw arrows to correctly identify the missing half of the relative plate motions for these flat Earth plate diagrams. I've drawn the arrows correctly on the attached sheet.
Part (a) (shown below) has two spreading centers and a transform fault connecting them. The primary important thing here is that you draw the relative motion across the transform fault correctly: top arrow pointing left, bottom arrow pointing right. Also, one arrow at each spreading center, both pointing right.
Part (b) (shown below) is identical to Example A on Handout 2.
Part (c) (shown below) was a bit somewhat more complicated. Here, there is a subduction zone on the right, with the plate on the right side overriding the plate on the left side. There are three spreading centers, with two transform faults connecting them. There are also two transform faults at the top and bottom, connecting the subduction zone and the upper and lower spreading centers, respectively. Again, you had to properly indicate relative motion across transform faults in order to get full credit.