Miquela and Gina drew orthographic drawings for the given cube structure. To decide who drew it correctly, we will do our own drawing and compare it with theirs. Remember that an orthographic drawing shows three separate views:

a top view,
a front view, and
a right-side view.

Top

We will start with the top view. Solid lines show visible edges.

Notice that the given cube structure has three columns in a row, from front to back, and then one more cube to the right, in line with the last column in the back.

Front

Now, we will draw the front view. Solid lines show visible edges and dashed lines show hidden edges.

From the front, we are able to see a height of three cubes in the left column and one cube in the right column. From the isometric drawing, we know that the column on the left, in the back, is shorter, which is why we have a dashed line.

Right

Finally, we will draw the right view. Again, solid lines show visible edges.

Conclusion

If we compare our orthographic drawing with the ones drawn by Miquela and Gina, we can see that we have the same drawing as Miquela. Therefore, she is the one who is correct.

Exercise

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