Please choose the correct ending to complete the given sentence: Computers and Electronics: [header] How to draw an impossible cube [title] Draw a skinny, vertical parallelogram with the lower left corner open; from there, draw two lines going horizontally, shown in red. [title] Add two connecting lines on the right side of the parallelogram. [step] They should form an " l ".

Ending1: [title] To the right side of the parallelogram, draw two larger smiley faces on either side. [step] These smiley faces will form segments on the small numbers. Ending2: [title] Draw two lines on both sides of the parallelogram to form a stalk. [step] The three lines should not touch each other. Ending3: [title] Add another two lines which continue from the corner of the parallelogram but pass beneath its right edge. [step] The two lines then separate vertically, one going up and another going down to meet with the end of the " l ". Ending4: Make sure to place one drawing side on top of another. They should have back marks on these lines, and the other side must be shaded in red.

Answer format: ending1/ending2/ending3/ending4