Mathematical Experiment 8

Draw a random spanning tree of {(x,y):x or
y
is an integer between 1 to n}

Draw a random spanning tree of {(x,y):x or y
is an integer between 1 to 30}\{(x,y): both x and
y
are between 12 to 18}.

The configuration drawn in the above problem can be regarded as a maze.
Draw its solution.

Draw the path of a light ray inside a perfectly reflective square.

Draw the path of a light ray inside a perfectly reflective ellipse.