Which of the following were true regarding class activities on Euclid's Proposition 11 (construct a perpendicular through a point on a line)
a) Fold the line on itself so that the fold goes through the point.
b) We used 3 circles in our Sketchpad construction.
c) We used SSS to show that we had right angles in the Sketchpad construction.
d) More than one of the above
e) All of a), b) and c)