One hot day, Stan, Kyle, and Kenny were sitting outside with a square watermelon (actually it was a cube like the picture below).
Stan says "Let's cut the watermelon into 3 equal slices (like the right-side diagram below)."
Kyle says "But then the end slices have more rind."
Can you show them how to cut this square watermelon into 3 equal (congruent) pieces, so that each piece has an equal amount of rind? The correct answer should include a sketch or a picture and uses just a few straight cuts (no tricks).